$ git clone -n https://src.fedoraproject.org/rpms/spdlog.git /var/lib/mock/f42-build-3272239-41305/root/chroot_tmpdir/scmroot/spdlog
Cloning into '/var/lib/mock/f42-build-3272239-41305/root/chroot_tmpdir/scmroot/spdlog'...
$ git fetch origin f74b4f9638de70df3413d48dcda358a8b5487b19:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/spdlog
 * [new ref]         f74b4f9638de70df3413d48dcda358a8b5487b19 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f74b4f9 Rebuilt due to fmt update.