$ git clone -n https://src.fedoraproject.org/rpms/R-openssl.git /var/lib/mock/f41-build-821113-152414/root/chroot_tmpdir/scmroot/R-openssl
Cloning into '/var/lib/mock/f41-build-821113-152414/root/chroot_tmpdir/scmroot/R-openssl'...
$ git fetch origin 5b3c836e7efc52934241c8fca16414a018e4c964:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-openssl
 * [new ref]         5b3c836e7efc52934241c8fca16414a018e4c964 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5b3c836 R-maint-sig mass rebuild