$ git clone -n https://src.fedoraproject.org/rpms/rust-servo_arc.git /var/lib/mock/f40-build-2643429-66488/root/chroot_tmpdir/scmroot/rust-servo_arc
Cloning into '/var/lib/mock/f40-build-2643429-66488/root/chroot_tmpdir/scmroot/rust-servo_arc'...
$ git fetch origin 64c7386e31e1a694d6a8e8645cdf8e9206d97461:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-servo_arc
 * [new ref]         64c7386e31e1a694d6a8e8645cdf8e9206d97461 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 64c7386 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild