$ git clone -n https://src.fedoraproject.org/rpms/R-openssl.git /var/lib/mock/f42-build-side-1-3501287-45974/root/chroot_tmpdir/scmroot/R-openssl
Cloning into '/var/lib/mock/f42-build-side-1-3501287-45974/root/chroot_tmpdir/scmroot/R-openssl'...
$ git fetch origin 989d9e8ce2248415320298195b2197ff6905d2bb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-openssl
 * [new ref]         989d9e8ce2248415320298195b2197ff6905d2bb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 989d9e8 R-maint-sig mass rebuild