$ git clone -n https://src.fedoraproject.org/rpms/mythes-cs.git /var/lib/mock/f45-build-19477-549/root/chroot_tmpdir/scmroot/mythes-cs
Cloning into '/var/lib/mock/f45-build-19477-549/root/chroot_tmpdir/scmroot/mythes-cs'...
$ git fetch origin 4f37c81f2e1c466414c3ce1469bd0ea1ca27438d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mythes-cs
 * [new ref]         4f37c81f2e1c466414c3ce1469bd0ea1ca27438d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4f37c81 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild