Ignore warning

setup.cfg

@@ -150,6 +150,7 @@ filterwarnings =
     # can be dropped with the next release of `certify`, specifically
     # `certify > 2022.06.15`.
     ignore:path is deprecated. Use files.. instead. Refer to https.//importlib-resources.readthedocs.io/en/latest/using.html#migrating-from-legacy for migration advice.:DeprecationWarning:certifi.core
+    ignore:Automatic charset detection will be removed in 3.9:DeprecationWarning
 junit_suite_name = aiohttp_test_suite
 norecursedirs = dist docs build .tox .eggs
 minversion = 3.8.2