Code review comment for ~nacc/git-ubuntu:importer-spi-refactoring

In queue.py:205, there is a repo.commit_tree_hash() call that wasn't modified to include the new fallback parameters, which do not default to None like the previous parameter spi did:
    commit_hash = repo.commit_tree_hash(
        tree_hash=tree_hash,
        parents=parents,
        log_message='Queue import'.encode(),
    )

Similarly, in build.py:833:
            fixup_commit_hash = repo.commit_tree_hash(
                tree_hash=tree_hash,
                parents=[commitish],
                log_message=b'Automatically generated git-ubuntu fixup.',
            )
            logging.info(
"""We automatically generated fixup changes relative to
%s as commit %s.
If you would like to create a branch at that commit, run:
\tgit checkout -b <branch name> %s""",
                commitish,
                fixup_commit_hash,
                fixup_commit_hash,
            )