Backport of #22533.
#21799 introduced a regression
where some links in the issue timeline were not muted any more. Fix it
by replacing all `class="text grey"` with `class="text grey
muted-links"` in the file.

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>

Backport #22551
There was an unintended regression in #21124 which assumed that
.commits-list .message-wrapper would only match the commit summaries on
/{owner}/{name}/commits/*. This assumption is incorrect as the
directory/file view also uses a .commits-list wrapper.

Rather than completely restructure this page this PR simply adjusts the
styling to again use display: inline-block; for #repo-files-table
.commit-list .message-wrapper

Fix #22360

Backport #22566

Change the mailer interface to prevent the leaking of possible hidden
email addresses when sending to multiple recipients.

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>
Co-authored-by: Gusted <williamzijl7@hotmail.com>

Signed-off-by: jolheiser <john.olheiser@gmail.com>