collection: Change default='no's and 'yes's to default=False and default=True (#556)

* Change default={'no','yes'} to default={False,True}

* Add changelog

* Remove changelog

plugins/modules/monitoring/datadog/datadog_event.py

@@ -115,7 +115,7 @@ def main():
                 choices=['error', 'warning', 'info', 'success']
             ),
             aggregation_key=dict(required=False, default=None),
-            validate_certs=dict(default='yes', type='bool'),
+            validate_certs=dict(default=True, type='bool'),
         )
     )