$ git clone -n https://src.fedoraproject.org/rpms/rust-tonic.git /var/lib/mock/f41-build-side-1-3006305-36744/root/chroot_tmpdir/scmroot/rust-tonic
Cloning into '/var/lib/mock/f41-build-side-1-3006305-36744/root/chroot_tmpdir/scmroot/rust-tonic'...
$ git fetch origin f88d347faf5cefa7437066ddad3e9aba92f92055:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-tonic
 * [new ref]         f88d347faf5cefa7437066ddad3e9aba92f92055 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f88d347 Update to version 0.12.3