Merge branch '439043-doc-project-archiving' into 'master'

Reorganize information about project archiving and transfer

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/143650



Merged-by: Peter Hegman <phegman@gitlab.com>
Approved-by: Christina Lohr <clohr@gitlab.com>
Approved-by: Peter Hegman <phegman@gitlab.com>
Reviewed-by: Lorena Ciutacu <lciutacu@gitlab.com>
Co-authored-by: Lorena Ciutacu <lciutacu@gitlab.com>