$ git clone -n https://src.fedoraproject.org/rpms/perl-System-Info.git /var/lib/mock/f39-build-1781235-41557/root/chroot_tmpdir/scmroot/perl-System-Info
Cloning into '/var/lib/mock/f39-build-1781235-41557/root/chroot_tmpdir/scmroot/perl-System-Info'...
$ git fetch origin 83f421cf5eabf49e4c029c77757602ab6448c13e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-System-Info
 * [new ref]         83f421cf5eabf49e4c029c77757602ab6448c13e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 83f421c 0.064 bump (rhbz#2227759)