Merge pull request #7270 from john-westcott-iv/fix_tower_settings_none

Prevent exception for Non value

Reviewed-by: https://github.com/apps/softwarefactory-project-zuul

awx_collection/plugins/modules/tower_settings.py

@@ -80,6 +80,10 @@ except ImportError:
 
 
 def coerce_type(module, value):
+    # If our value is already None we can just return directly
+    if value is None:
+        return value
+
     yaml_ish = bool((
         value.startswith('{') and value.endswith('}')
     ) or (