$ git clone -n https://src.fedoraproject.org/rpms/libXcomposite.git /var/lib/mock/f45-build-15760-479/root/chroot_tmpdir/scmroot/libXcomposite
Cloning into '/var/lib/mock/f45-build-15760-479/root/chroot_tmpdir/scmroot/libXcomposite'...
$ git fetch origin d03a4959a189b216e6eff4bbd14108291f27ecc9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libXcomposite
 * [new ref]         d03a4959a189b216e6eff4bbd14108291f27ecc9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d03a495 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild