Check for technical support contacts as part of new hub turn-up

As part of 2i2c-org#3048 (comment),
we now have an airtable be the 'source of truth' for who is
allowed to initiate support requests. This PR adds an item in
the checklist for new hub turn up, making sure we validate that
there *is* a technical contact for this hub.

The airtable in use may change soon as well as the terminology
(as partnerships works on it 2i2c-org#3048 (comment)).
But it is important to have a verification step here, so we don't
let whatever airtable it is be out of date.

Ref 2i2c-org#3048 (comment)

.github/ISSUE_TEMPLATE/2_new-hub-provide-info.yml

@@ -172,6 +172,20 @@ body:
     validations:
       required: false
 
+  - type: checkboxes
+    attributes:
+      label: Technical support contacts listed
+      description: |
+        Technical contacts are the folks who are authorized to open support tickets about this hub.
+        The source of truth is maintained in [this airtable](https://airtable.com/appxk7c9WUsDjSi0Q/tbl3CWOgyoEtuGuIw/viwtpo7RxkYv63hiD?blocks=hide).
+
+        Validate that there is at least one technical contact listed in the airtable for this hub. If not, ping
+        partnerships to ensure they find out who that is and fill that information in.
+      options:
+        - label: Technical contact present
+    validations:
+      required: true
+
   - type: dropdown
     attributes:
       label: (Optional) Preferred cloud provider