rm unnecessary test config

Author: eli-bl

end_to_end_tests/docstrings_on_attributes.config.yml

@@ -1,15 +1 @@
-class_overrides:
-  _ABCResponse:
-    class_name: ABCResponse
-    module_name: abc_response
-  AnEnumValueItem:
-    class_name: AnEnumValue
-    module_name: an_enum_value
-  NestedListOfEnumsItemItem:
-    class_name: AnEnumValue
-    module_name: an_enum_value
-field_prefix: attr_
-content_type_overrides:
-  openapi/python/client: application/json
-generate_all_tags: true
 docstrings_on_attributes: true