$ git clone -n https://src.fedoraproject.org/rpms/rust-icu_collections.git /var/lib/mock/f42-build-side-1-3581411-46829/root/chroot_tmpdir/scmroot/rust-icu_collections
Cloning into '/var/lib/mock/f42-build-side-1-3581411-46829/root/chroot_tmpdir/scmroot/rust-icu_collections'...
$ git fetch origin 61c050a87e2e6e4932ccadcea8ce29e0afee5f98:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-icu_collections
 * [new ref]         61c050a87e2e6e4932ccadcea8ce29e0afee5f98 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 61c050a Restore postcard dev-dependency