$ git clone -n https://src.fedoraproject.org/rpms/grpc.git /var/lib/mock/f41-build-808424-145851/root/chroot_tmpdir/scmroot/grpc
Cloning into '/var/lib/mock/f41-build-808424-145851/root/chroot_tmpdir/scmroot/grpc'...
$ git fetch origin a4b70e8b1067909dcaa867a9ac09e68fd6b2508a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/grpc
 * [new ref]         a4b70e8b1067909dcaa867a9ac09e68fd6b2508a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a4b70e8 - Rebuilt for libre2.so.11 bump