$ git clone -n https://src.fedoraproject.org/rpms/credentials-fetcher.git /var/lib/mock/f42-build-3494625-45873/root/chroot_tmpdir/scmroot/credentials-fetcher
Cloning into '/var/lib/mock/f42-build-3494625-45873/root/chroot_tmpdir/scmroot/credentials-fetcher'...
$ git fetch origin 4c8196644cdf5791b977d76ea2bc812a3e067eee:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/credentials-fetcher
 * [new ref]         4c8196644cdf5791b977d76ea2bc812a3e067eee -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4c81966 Rebuild (abseil-cpp)