Revert adding @maxking to CODEOWNERS file (pythonGH-13660)

This reverts commit 71dc7c5. Turns out you must have write access for CODEOWNERS to work.

Author: brettcannon

.github/CODEOWNERS

@@ -44,7 +44,7 @@ Objects/dict*                 @methane
 Python/bootstrap_hash.c       @python/crypto-team @tiran
 
 # Email and related
-**/*mail*                     @python/email-team @maxking
+**/*mail*                     @python/email-team
 **/*smtp*                     @python/email-team
 **/*mime*                     @python/email-team
 **/*imap*                     @python/email-team