$ git clone -n https://src.fedoraproject.org/rpms/kf6-kbookmarks.git /var/lib/mock/f40-build-787185-134736/root/chroot_tmpdir/scmroot/kf6-kbookmarks
Cloning into '/var/lib/mock/f40-build-787185-134736/root/chroot_tmpdir/scmroot/kf6-kbookmarks'...
$ git fetch origin 40b870f975a5c612673acac2f1d66b7b365afade:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kf6-kbookmarks
 * [new ref]         40b870f975a5c612673acac2f1d66b7b365afade -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 40b870f 6.0.0