sns_topic boto3 port (#39292)

* Port sns_topic to boto3 and add tests

test/integration/targets/sns_topic/files/sns_topic_lambda/sns_topic_lambda.py

@@ -0,0 +1,6 @@
+from __future__ import print_function
+
+
+def handler(event, context):
+    print(event)
+    return True