$ git clone -n https://src.fedoraproject.org/rpms/python-blivet.git /var/lib/mock/f41-build-side-1-2905900-34717/root/chroot_tmpdir/scmroot/python-blivet
Cloning into '/var/lib/mock/f41-build-side-1-2905900-34717/root/chroot_tmpdir/scmroot/python-blivet'...
$ git fetch origin 031d575300fbcb2223d5096bb9fed59cf8aebfa3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-blivet
 * [new ref]         031d575300fbcb2223d5096bb9fed59cf8aebfa3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 031d575 free_space_estimate: adjust for compression on btrfs (#2315638)