Merge branch 'ms-fix-mail-smtp-defaults-override' into 'master'

Prevents Mail::SMTP monkey patch from overriding defaults

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/130185



Merged-by: Stan Hu <stanhu@gmail.com>
Approved-by: Heinrich Lee Yu <heinrich@gitlab.com>
Approved-by: Stan Hu <stanhu@gmail.com>
Reviewed-by: Heinrich Lee Yu <heinrich@gitlab.com>
Reviewed-by: Marc Saleiko <msaleiko@gitlab.com>
Co-authored-by: Marc Saleiko <msaleiko@gitlab.com>