sns_topic: Allow canonical international-format phone numbers in SMS …

…subscriptions (ansible-collections#454)

* Update sns_topic.py

Adds `+` to the list of acceptable characters in an SMS endpoint.

Closes ansible-collections#453.

* Add changelog fragment for ansible-collections#454

* sns_topic: comment explaining SMS canonicalization

Add comment documenting to what standard SMS endpoint addresses (phone
numbers) are canonicalized

* sns_topic: fix changelog

* Get quoting correct
* Simplify message to leave details in PR description

Co-authored-by: Mark Chappell <mchappel@redhat.com>

Co-authored-by: Mark Chappell <mchappel@redhat.com>

sns_topic.py

@@ -349,8 +349,11 @@ def _set_topic_attrs(self):
         return changed
 
     def _canonicalize_endpoint(self, protocol, endpoint):
+        # AWS SNS expects phone numbers in
+        # and canonicalizes to E.164 format
+        # See <https://docs.aws.amazon.com/sns/latest/dg/sms_publish-to-phone.html>
         if protocol == 'sms':
-            return re.sub('[^0-9]*', '', endpoint)
+            return re.sub('[^0-9+]*', '', endpoint)
         return endpoint
 
     def _set_topic_subs(self):