$ git clone -n https://src.fedoraproject.org/rpms/R-gapminder.git /var/lib/mock/f40-build-1944412-25177/root/chroot_tmpdir/scmroot/R-gapminder
Cloning into '/var/lib/mock/f40-build-1944412-25177/root/chroot_tmpdir/scmroot/R-gapminder'...
$ git fetch origin de956ba820b9372eba28dc11f2b692dc3de7dad3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-gapminder
 * [new ref]         de956ba820b9372eba28dc11f2b692dc3de7dad3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at de956ba R-maint-sig mass rebuild