Rename post-201-response.md to post201-response.md to match kebab case file naming convention (#774)

Author: danieljurek

docs/post-201-response.md renamed to docs/post201-response.md

@@ -946,7 +946,7 @@ Please refer to [path-resource-type-name-camel-case.md](./path-resource-type-nam
 
 Using post for a create operation is discouraged.
 
-Please refer to [post-201-response.md](./post-201-response.md) for details.
+Please refer to [post201-response.md](./post201-response.md) for details.
 
 ### PostOperationIdContainsUrlVerb