$ git clone -n https://src.fedoraproject.org/rpms/libmp4v2.git /var/lib/mock/f45-build-16605-488/root/chroot_tmpdir/scmroot/libmp4v2
Cloning into '/var/lib/mock/f45-build-16605-488/root/chroot_tmpdir/scmroot/libmp4v2'...
$ git fetch origin 3162ca52aa56d0eb60619edee2b7d8f29279ac37:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libmp4v2
 * [new ref]         3162ca52aa56d0eb60619edee2b7d8f29279ac37 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3162ca5 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild