Add description for scm

Changed double quotes to single quotes on scm description to see if that impacts the failing api schema test

Move descriptions manually added together for easier readability

awx/main/utils/plugins.py

@@ -76,8 +76,10 @@ def load_combined_inventory_source_options() -> dict[str, str]:
 
     plugin_description = discover_available_cloud_provider_descriptions()
 
-    result = {plugin: plugin_description.get(plugin, plugin) for plugin in plugins}
+    plugin_description['scm'] = 'Sourced from a Project'
+
+    plugin_description['file'] = 'File-based inventory source'
 
-    result['file'] = 'File-based inventory source'
+    result = {plugin: plugin_description.get(plugin, plugin) for plugin in plugins}
 
     return result