fix(cdn): restrict CDN region check lookup (#798)

Limits the CDN region check for logging to only
run during the cdn template deployment.
Previously this would run on resource group
deployments that deploy to the default region

aws/components/cdn/setup.ftl

@@ -791,15 +791,19 @@
     [#if wafPresent ]
         [#if solution.WAF.Logging.Enabled]
 
-            [#if getRegion() != "us-east-1" ]
-                [@fatal
-                    message="To enable firehose based logging for WAF on CDN the deployment must be run from us-east-1"
-                    context={
-                        "CDNId" : occurrence.Core.Id,
-                        "Region" : getRegion()
-                    }
-                /]
-            [/#if]
+            [#if deploymentSubsetRequired(CDN_COMPONENT_TYPE, true)]
+
+                [#if getRegion() != "us-east-1" ]
+                    [@fatal
+                        message="To enable firehose based logging for WAF on CDN the deployment must be run from us-east-1"
+                        context={
+                            "CDNId" : occurrence.Core.Id,
+                            "Region" : getRegion()
+                        }
+                    /]
+                [/#if]
+
+            [/#if ]
 
             [#local wafFirehoseStreamId =
                 formatResourceId(AWS_KINESIS_FIREHOSE_STREAM_RESOURCE_TYPE, wafAclId)]