Merge branch 'cb-deb-10-deprecation-docs' into 'master'

Omnibus docs: Move Debian 10 to deprecated OSes

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/169249



Merged-by: Evan Read <eread@gitlab.com>
Approved-by: Evan Read <eread@gitlab.com>
Co-authored-by: Clemens Beck <cbeck@gitlab.com>