[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/pickletester.py b/Lib/test/pickletester.py
index 25283f8..3e2c781 100644
--- a/Lib/test/pickletester.py
+++ b/Lib/test/pickletester.py
@@ -3723,7 +3723,7 @@ class MyClass:
 
                 self.assertEqual(new_f, 5)
                 self.assertEqual(some_str, 'some str')
-                # math.log does not have its usual reducer overriden, so the
+                # math.log does not have its usual reducer overridden, so the
                 # custom reduction callback should silently direct the pickler
                 # to the default pickling by attribute, by returning
                 # NotImplemented
@@ -3740,7 +3740,7 @@ class MyClass:
     def test_reducer_override_no_reference_cycle(self):
         # bpo-39492: reducer_override used to induce a spurious reference cycle
         # inside the Pickler object, that could prevent all serialized objects
-        # from being garbage-collected without explicity invoking gc.collect.
+        # from being garbage-collected without explicitly invoking gc.collect.
 
         for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
             with self.subTest(proto=proto):