$ git clone -n https://src.fedoraproject.org/rpms/kf6-kwindowsystem.git /var/lib/mock/f42-build-side-1-3502572-45978/root/chroot_tmpdir/scmroot/kf6-kwindowsystem
Cloning into '/var/lib/mock/f42-build-side-1-3502572-45978/root/chroot_tmpdir/scmroot/kf6-kwindowsystem'...
$ git fetch origin 677b19b1c8208e1e82d89e1050e0b71b1f1e5714:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kwindowsystem
 * [new ref]         677b19b1c8208e1e82d89e1050e0b71b1f1e5714 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 677b19b Rebuild (qt6)