$ git clone -n https://src.fedoraproject.org/rpms/mesa-demos.git /var/lib/mock/f39-build-1902287-42864/root/chroot_tmpdir/scmroot/mesa-demos
Cloning into '/var/lib/mock/f39-build-1902287-42864/root/chroot_tmpdir/scmroot/mesa-demos'...
$ git fetch origin 6b283055f3580353715815db5714fa40e5e8bb5b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mesa-demos
 * [new ref]         6b283055f3580353715815db5714fa40e5e8bb5b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6b28305 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild