Fix the valid types check for `Any in sphinx.config`

tests/test_config/test_config.py

@@ -5,7 +5,7 @@ import pickle
 import time
 from collections import Counter
 from pathlib import Path
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Any
 from unittest import mock
 
 import pytest
@@ -552,6 +552,14 @@ def test_check_enum_for_list_failed(logger):
     assert logger.warning.called
 
 
+@mock.patch("sphinx.config.logger")
+def test_check_any(logger):
+    config = Config({'value': None})
+    config.add('value', 'default', '', Any)
+    check_confval_types(None, config)
+    logger.warning.assert_not_called()  # not warned
+
+
 nitpick_warnings = [
     "WARNING: py:const reference target not found: prefix.anything.postfix",
     "WARNING: py:class reference target not found: prefix.anything",