$ git clone -n https://src.fedoraproject.org/rpms/rust-http.git /var/lib/mock/f40-build-2520894-61797/root/chroot_tmpdir/scmroot/rust-http
Cloning into '/var/lib/mock/f40-build-2520894-61797/root/chroot_tmpdir/scmroot/rust-http'...
$ git fetch origin fc404ff114193f7a69ae81c222d24ba3caa333c3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-http
 * [new ref]         fc404ff114193f7a69ae81c222d24ba3caa333c3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fc404ff Update to version 1.1.0; Fixes RHBZ#2267747