Update references to match upstream

Author: jaraco

Doc/library/importlib.metadata.rst

@@ -397,4 +397,4 @@ a custom finder, return instances of this derived ``Distribution`` in the
 
 .. _`entry point API`: https://setuptools.readthedocs.io/en/latest/pkg_resources.html#entry-points
 .. _`metadata API`: https://setuptools.readthedocs.io/en/latest/pkg_resources.html#metadata-api
-.. _`importlib_resources`: https://importlib-resources.readthedocs.io/en/latest/index.html
+.. _`finders`: https://docs.python.org/3/reference/import.html#finders-and-loaders