$ git clone -n https://src.fedoraproject.org/rpms/gimp.git /var/lib/mock/f42-build-3322614-41426/root/chroot_tmpdir/scmroot/gimp
Cloning into '/var/lib/mock/f42-build-3322614-41426/root/chroot_tmpdir/scmroot/gimp'...
$ git fetch origin c9151ca1af4f8293cfde45ec1c89fec3074ca30b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gimp
 * [new ref]         c9151ca1af4f8293cfde45ec1c89fec3074ca30b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c9151ca Bump required gegl version