Add setuptools reference in comments

pypa/setuptools#4254

stubs/setuptools/pkg_resources/__init__.pyi

@@ -337,14 +337,14 @@ class NullProvider:
     def has_resource(self, resource_name: str) -> bool: ...
     # Note: runtime forgets to coerce the return type to boolean,
     # but we need to specify bool for NullProvider to respect the IResourceProvider protocol
-    # TODO: raise and fix in setuptools' repo
+    # https://github.com/pypa/setuptools/pull/4254
     def has_metadata(self, name: str) -> bool: ...
     def get_metadata(self, name: str) -> str: ...
     def get_metadata_lines(self, name: str) -> chain[str]: ...
     def resource_isdir(self, resource_name: str) -> bool: ...
     # Note: runtime forgets to coerce the return type to boolean,
     # but we need to specify bool for NullProvider to respect the IResourceProvider protocol
-    # TODO: raise and fix in setuptools' repo
+    # https://github.com/pypa/setuptools/pull/4254
     def metadata_isdir(self, name: str) -> bool: ...
     def resource_listdir(self, resource_name: str) -> list[str]: ...
     def metadata_listdir(self, name: str) -> list[str]: ...