Prevent exception for Non value

awx_collection/plugins/modules/tower_settings.py

@@ -82,6 +82,10 @@ except ImportError:
 
 
 def coerce_type(module, value):
+    # If our value is already None we can just return directly
+    if value == None:
+        return value
+
     yaml_ish = bool((
         value.startswith('{') and value.endswith('}')
     ) or (

awx_collection/tests/integration/targets/tower_settings/tasks/main.yml

@@ -74,3 +74,9 @@
 - assert:
     that:
       - "result is changed"
+
+- name: Handle an omit value
+  tower_settings:
+    name: AWX_PROOT_BASE_PATH
+    value: '{{ junk_var | default(omit) }}'
+