[3.10] Fix typos in the Lib directory (GH-28775) (GH-28804)

Fix typos in the Lib directory as identified by codespell.

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>.
(cherry picked from commit 745c9d9dfc1ad6fdfdf1d07420c6273ff67fa5be)

Co-authored-by: Christian Clauss <cclauss@me.com>
diff --git a/Lib/test/test_wsgiref.py b/Lib/test/test_wsgiref.py
index 93ca6b9..42094f4 100644
--- a/Lib/test/test_wsgiref.py
+++ b/Lib/test/test_wsgiref.py
@@ -580,7 +580,7 @@ def testEnviron(self):
         # Test handler.environ as a dict
         expected = {}
         setup_testing_defaults(expected)
-        # Handler inherits os_environ variables which are not overriden
+        # Handler inherits os_environ variables which are not overridden
         # by SimpleHandler.add_cgi_vars() (SimpleHandler.base_env)
         for key, value in os_environ.items():
             if key not in expected: