$ git clone -n https://src.fedoraproject.org/rpms/gnubik.git /var/lib/mock/f39-build-1462054-33299/root/chroot_tmpdir/scmroot/gnubik
Cloning into '/var/lib/mock/f39-build-1462054-33299/root/chroot_tmpdir/scmroot/gnubik'...
$ git fetch origin e1907a2c6510386670ed47c36d8548543a3fa0c7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnubik
 * [new ref]         e1907a2c6510386670ed47c36d8548543a3fa0c7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e1907a2 Remove obsolete requirements for %post/%preun scriptlets