$ git clone -n https://src.fedoraproject.org/rpms/anaconda.git /var/lib/mock/f42-build-864508-172369/root/chroot_tmpdir/scmroot/anaconda
Cloning into '/var/lib/mock/f42-build-864508-172369/root/chroot_tmpdir/scmroot/anaconda'...
$ git fetch origin 2eeeeac26717a21c6deab05fc42e5255e4e82ae0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/anaconda
 * [new ref]         2eeeeac26717a21c6deab05fc42e5255e4e82ae0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2eeeeac Update to 42.21 upstream release