Merge branch 'remove-unused-eager-fetch-ref-method' into 'master'

Remove unused method MergeRequest#eager_fetch_ref!

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/146247



Merged-by: Gary Holtz <gholtz@gitlab.com>
Approved-by: Aman Luthra <aluthra@gitlab.com>
Approved-by: Gary Holtz <gholtz@gitlab.com>
Reviewed-by: Gary Holtz <gholtz@gitlab.com>
Co-authored-by: Hordur Freyr Yngvason <hfyngvason@gitlab.com>