Add list of valid connectors to alerting rules docs

docs/en/observability/infrastructure-threshold-alert.asciidoc

@@ -49,10 +49,10 @@ image::images/alert-preview.png[Preview rules]
 [[action-types-infrastructure]]
 == Action types
 
-You can extend your rules by connecting them to actions that use the following supported built-in integrations.
+Extend your rules by connecting them to actions that use the following supported built-in integrations.
+
+include::../shared/alerting-connectors.asciidoc[]
 
-[role="screenshot"]
-image::images/alert-action-types.png[Action types]
 
 After you select a connector, you must set the action frequency. You can choose to create a summary of alerts on each check interval or on a custom interval. For example, send email notifications that summarize the new, ongoing, and recovered alerts each hour:
 

docs/en/observability/logs-threshold-alert.asciidoc

@@ -108,8 +108,7 @@ ratio. In this scenario, no alert is triggered.
 
 Extend your rules by connecting them to actions that use the following supported built-in integrations.
 
-[role="screenshot"]
-image::images/alert-action-types.png[Alert action types]
+include::../shared/alerting-connectors.asciidoc[]
 
 After you select a connector, you must set the action frequency. You can choose to create a summary of alerts on each check interval or on a custom interval. Alternatively, you can set the action frequency such that you choose how often the action runs (for example, at each check interval, only when the alert status changes, or at a custom action interval). In this case, you must also select the specific threshold condition that affects when actions run: `Fired` or `Recovered`.
 

docs/en/observability/metrics-threshold-alert.asciidoc

@@ -66,10 +66,9 @@ The default value is `1`.
 [[action-types-metrics]]
 == Action types
 
-You can extend your rules by connecting them to actions that use supported built-in integrations.
+Extend your rules by connecting them to actions that use the following supported built-in integrations.
 
-[role="screenshot"]
-image::images/alert-action-types.png[Action types]
+include::../shared/alerting-connectors.asciidoc[]
 
 After you select a connector, you must set the action frequency. You can choose to create a summary of alerts on each check interval or on a custom interval. For example, send email notifications that summarize the new, ongoing, and recovered alerts each hour:
 

docs/en/observability/slo-burn-rate-alert.asciidoc

@@ -32,14 +32,13 @@ To create your SLO burn rate rule:
 [[action-types-slo]]
 == Action types
 
-You can extend your rules by connecting them to actions that use the following
+Extend your rules by connecting them to actions that use the following
 supported built-in integrations. Actions are {kib} services or integrations with
 third-party systems that run as background tasks on the {kib} server when rule conditions are met.
 
 You can configure action types on the <<configure-uptime-alert-connectors,Settings>> page.
 
-[role="screenshot"]
-image::images/alert-action-types.png[Uptime rule connectors]
+include::../shared/alerting-connectors.asciidoc[]
 
 After you select a connector, you must set the action frequency. You can choose to create a *Summary of alerts* on each check interval or on a custom interval. For example, you can send email notifications that summarize the new, ongoing, and recovered alerts every twelve hours.
 

docs/en/observability/threshold-alert.asciidoc

@@ -127,8 +127,7 @@ For example when it's set to `Logs`, you must have the appropriate *{observabili
 
 Extend your rules by connecting them to actions that use the following supported built-in integrations.
 
-[role="screenshot"]
-image::images/alert-action-types.png[Alert action types]
+include::../shared/alerting-connectors.asciidoc[]
 
 After you select a connector, you must set the action frequency. You can choose to create a summary of alerts on each check interval or on a custom interval. Alternatively, you can set the action frequency such that you choose how often the action runs (for example, at each check interval, only when the alert status changes, or at a custom action interval). In this case, you must also select the specific threshold condition that affects when actions run: `Alert`, `No Data`, or `Recovered`.
 

docs/en/observability/uptime-duration-anomaly-alert.asciidoc

@@ -42,14 +42,15 @@ image::images/response-durations-alert.png[Uptime response duration rule]
 [[action-types-duration]]
 == Action types
 
-You can extend your rules by connecting them to actions that use the following
+Extend your rules by connecting them to actions that use the following
 supported built-in integrations. Actions are {kib} services or integrations with
 third-party systems that run as background tasks on the {kib} server when rule conditions are met.
 
+//TODO: Make this intro consistent across topics. Should we define action here?
+
 You can configure action types on the <<configure-uptime-alert-connectors,Settings>> page.
 
-[role="screenshot"]
-image::images/alert-action-types.png[Uptime rule connectors]
+include::../shared/alerting-connectors.asciidoc[]
 
 After you select a connector, you must set the action frequency. You can choose to create a summary of alerts on each check interval or on a custom interval. For example, send email notifications that summarize the new, ongoing, and recovered alerts every twelve hours:
 

docs/en/observability/uptime-tls-alert.asciidoc

@@ -40,14 +40,13 @@ image::images/tls-alert.png[Monitor status rule]
 [[action-types-certs]]
 == Action types
 
-You can extend your rules by connecting them to actions that use the following
+Extend your rules by connecting them to actions that use the following
 supported built-in integrations. Actions are {kib} services or integrations with
 third-party systems that run as background tasks on the {kib} server when rule conditions are met.
 
 You can configure action types on the <<configure-uptime-alert-connectors,Settings>> page.
 
-[role="screenshot"]
-image::images/alert-action-types.png[TLS certificate rule connectors]
+include::../shared/alerting-connectors.asciidoc[]
 
 After you select a connector, you must set the action frequency. You can choose to create a summary of alerts on each check interval or on a custom interval. Alternatively, you can set the action frequency such that you choose how often the action runs (for example, at each check interval, only when the alert status changes, or at a custom action interval). In this case, you must also select the specific threshold condition that affects when actions run: `Uptime TLS Alert` or `Recovered`. For example, send a notification when an alert status changes:
 

docs/en/shared/alerting-connectors.asciidoc

@@ -0,0 +1,24 @@
+* {kibana-ref}/d3security-action-type.html[D3 Security]
+* {kibana-ref}/email-action-type.html[Email]
+* {kibana-ref}/resilient-action-type.html[{ibm-r}]
+* {kibana-ref}/index-action-type.html[Index]
+* {kibana-ref}/jira-action-type.html[Jira]
+* {kibana-ref}/teams-action-type.html[Microsoft Teams]
+* {kibana-ref}/opsgenie-action-type.html[{opsgenie}]
+* {kibana-ref}/pagerduty-action-type.html[PagerDuty]
+* {kibana-ref}/server-log-action-type.html[ServerLog]
+* {kibana-ref}/servicenow-itom-action-type.html[{sn-itom}]
+* {kibana-ref}/servicenow-action-type.html[{sn-itsm}]
+* {kibana-ref}/servicenow-sir-action-type.html[{sn-sir}]
+* {kibana-ref}/slack-action-type.html[Slack]
+* {kibana-ref}/swimlane-action-type.html[{swimlane}]
+* {kibana-ref}/torq-action-type.html[Torq]
+* {kibana-ref}/webhook-action-type.html[{webhook}]
+* {kibana-ref}/xmatters-action-type.html[xMatters]
+
+[NOTE]
+==============================================
+Some connector types are paid commercial features, while others are free.
+For a comparison of the Elastic subscription levels, go to
+{subscriptions}[the subscription page].
+==============================================