$ git clone -n https://src.fedoraproject.org/rpms/plasma-breeze.git /var/lib/mock/f42-build-side-1-3505171-45989/root/chroot_tmpdir/scmroot/plasma-breeze
Cloning into '/var/lib/mock/f42-build-side-1-3505171-45989/root/chroot_tmpdir/scmroot/plasma-breeze'...
$ git fetch origin b3ff2c4082777a411739bd46629fad3c5607090a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-breeze
 * [new ref]         b3ff2c4082777a411739bd46629fad3c5607090a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b3ff2c4 6.3.4