$ git clone -n http://fedora.riscv.rocks:3000/rpms/R-stringr.git /var/lib/mock/f41-build-838789-159768/root/chroot_tmpdir/scmroot/R-stringr
Cloning into '/var/lib/mock/f41-build-838789-159768/root/chroot_tmpdir/scmroot/R-stringr'...
$ git fetch origin 8421303b9c5e14c217797f7403fedc8ef354cdc8:KOJI_FETCH_HEAD
From http://fedora.riscv.rocks:3000/rpms/R-stringr
 * [new ref]         8421303b9c5e14c217797f7403fedc8ef354cdc8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8421303 Enable bootstrap