$ git clone -n https://src.fedoraproject.org/rpms/rust-sharded-slab.git /var/lib/mock/f40-build-2083738-49961/root/chroot_tmpdir/scmroot/rust-sharded-slab
Cloning into '/var/lib/mock/f40-build-2083738-49961/root/chroot_tmpdir/scmroot/rust-sharded-slab'...
$ git fetch origin a354ea27c94c34733bd39b7a2ee22b1feb25a37d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-sharded-slab
 * [new ref]         a354ea27c94c34733bd39b7a2ee22b1feb25a37d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a354ea2 Update to version 0.1.7; Fixes RHBZ#2241079