$ git clone -n https://src.fedoraproject.org/rpms/xmlrpc-c.git /var/lib/mock/f45-build-38960-730/root/chroot_tmpdir/scmroot/xmlrpc-c
Cloning into '/var/lib/mock/f45-build-38960-730/root/chroot_tmpdir/scmroot/xmlrpc-c'...
$ git fetch origin beddf7cc75be77da011cdc3aacf1830a41a9c5b2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xmlrpc-c
 * [new ref]         beddf7cc75be77da011cdc3aacf1830a41a9c5b2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at beddf7c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild