$ git clone -n https://src.fedoraproject.org/rpms/libmp4v2.git /var/lib/mock/f39-build-1535726-36247/root/chroot_tmpdir/scmroot/libmp4v2
Cloning into '/var/lib/mock/f39-build-1535726-36247/root/chroot_tmpdir/scmroot/libmp4v2'...
$ git fetch origin c43a2cb3e794ad21b7d263fcc9e1efcc673ac45e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libmp4v2
 * [new ref]         c43a2cb3e794ad21b7d263fcc9e1efcc673ac45e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c43a2cb Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild