George Koltsov authored Jun 08, 2022 and Luke Duncalfe committed Jun 08, 2022

  - Replace repository import from `fetch_as_mirror` to be using
    repository bundle during GitLab Migration in order to have
    closer feature parity with file-based Import/Export, as repo
    bundle has keep-around refs present, which are required in
    situations when source branch is deleted (e.g. merged/closed
    MRs with diff notes and source branch is removed).

#358776