$ git clone -n https://src.fedoraproject.org/rpms/rust-sharded-slab.git /var/lib/mock/f45-build-44915-819/root/chroot_tmpdir/scmroot/rust-sharded-slab
Cloning into '/var/lib/mock/f45-build-44915-819/root/chroot_tmpdir/scmroot/rust-sharded-slab'...
$ git fetch origin af0807feed4604e4fdccc9f9671b8c8638e4392d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-sharded-slab
 * [new ref]         af0807feed4604e4fdccc9f9671b8c8638e4392d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at af0807f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild