pyupgrade: drop `coding=UTF-8` comments PEP-3120[1] (Python 3.0 in 2007) says that UTF-8 is the default encoding. That should be long enough ago that no reasonable editor would trip over this, and certainly any supported version of Python won't. The comments were probably harmless, but as `pyupgrade` has no mechanism to disable this change, omitting this change makes it unusable as a code checking tool, and makes it a pain to use occasionally to upgrade the source (since these changes would need to be manually reverted). [1] https://peps.python.org/pep-3120/

--- a/mercurial/revlogutils/rewrite.py	Mon Jan 06 01:39:53 2025 -0500
+++ b/mercurial/revlogutils/rewrite.py	Tue Jan 07 16:46:21 2025 -0500
@@ -1,5 +1,4 @@
 # censor code related to censoring revision
-# coding: utf8
 #
 # Copyright 2021 Pierre-Yves David <pierre-yves.david@octobus.net>
 # Copyright 2015 Google, Inc <martinvonz@google.com>