$ git clone -n https://src.fedoraproject.org/rpms/R-munsell.git /var/lib/mock/f42-build-side-1-3501681-45976/root/chroot_tmpdir/scmroot/R-munsell
Cloning into '/var/lib/mock/f42-build-side-1-3501681-45976/root/chroot_tmpdir/scmroot/R-munsell'...
$ git fetch origin c0ab89a58f803b21c68a817617380f54b6b3144c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-munsell
 * [new ref]         c0ab89a58f803b21c68a817617380f54b6b3144c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c0ab89a R-maint-sig mass rebuild