$ git clone -n https://src.fedoraproject.org/rpms/rust-deflate64.git /var/lib/mock/f39-build-1641039-40165/root/chroot_tmpdir/scmroot/rust-deflate64
Cloning into '/var/lib/mock/f39-build-1641039-40165/root/chroot_tmpdir/scmroot/rust-deflate64'...
$ git fetch origin 5ccc5b42e87dfa5a7bb55f87f9dfb307116da284:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-deflate64
 * [new ref]         5ccc5b42e87dfa5a7bb55f87f9dfb307116da284 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5ccc5b4 Update to version 0.1.6; Fixes RHBZ#2244257