Issue #27076: Doc, comment and test function name spelling fixes

Most fixes to Doc/ and Lib/ directories by Ville Skyttä.
diff --git a/Lib/test/test_winsound.py b/Lib/test/test_winsound.py
index 4208fe7..c94a4dc 100644
--- a/Lib/test/test_winsound.py
+++ b/Lib/test/test_winsound.py
@@ -159,7 +159,7 @@
             )
 
     def test_alias_fallback(self):
-        # In the absense of the ability to tell if a sound was actually
+        # In the absence of the ability to tell if a sound was actually
         # played, this test has two acceptable outcomes: success (no error,
         # sound was theoretically played; although as issue #19987 shows
         # a box without a soundcard can "succeed") or RuntimeError.  Any