$ git clone -n https://src.fedoraproject.org/rpms/mbuffer.git /var/lib/mock/f39-build-1520647-35831/root/chroot_tmpdir/scmroot/mbuffer
Cloning into '/var/lib/mock/f39-build-1520647-35831/root/chroot_tmpdir/scmroot/mbuffer'...
$ git fetch origin 51b93c1bbed2acbe4846ade95c5db7e4d9d26025:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mbuffer
 * [new ref]         51b93c1bbed2acbe4846ade95c5db7e4d9d26025 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 51b93c1 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild