Fix linter issue.

Author: WaVEV

django_mongodb/compiler.py

@@ -220,10 +220,6 @@ def _get_ordering(self):
     def collection_name(self):
         return self.query.get_meta().db_table
 
-    @cached_property
-    def collection_name(self):
-        return self.query.get_meta().db_table
-
     def get_collection(self):
         return self.connection.get_collection(self.collection_name)