Diffing against last commit can fail in `incremental_files_only` after a force push

[jonathandung]

Interestingly, the workflow step succeeded despite printing the error, but I expected the entire workflow to terminate at that point.

Output:

2026-09-28T03:50:17.8049165Z ##[group]Run streetsidesoftware/cspell-action@6f3c77c1406bc930f944ba97e9801a22e42caf58
2026-09-28T03:50:17.8049641Z with:
2026-09-28T03:50:17.8049850Z   config: cspell.json
2026-09-28T03:50:17.8050094Z   incremental_files_only: true
2026-09-28T03:50:17.8050345Z   inline: warning
2026-09-28T03:50:17.8050582Z   treat_flagged_words_as_errors: false
2026-09-28T03:50:17.8050855Z   strict: true
2026-09-28T03:50:17.8051072Z   suggestions: false
2026-09-28T03:50:17.8051506Z   verbose: false
2026-09-28T03:50:17.8051727Z   check_dot_files: explicit
2026-09-28T03:50:17.8051976Z   use_cspell_files: false
2026-09-28T03:50:17.8052206Z   summary: false
2026-09-28T03:50:17.8052406Z env:
2026-09-28T03:50:17.8052683Z   UV_PYTHON_INSTALL_DIR: /home/runner/work/_temp/uv-python-dir
2026-09-28T03:50:17.8053031Z   UV_PYTHON: 3.15
2026-09-28T03:50:17.8053311Z   VIRTUAL_ENV: /home/runner/work/asyncutils/asyncutils/.venv
2026-09-28T03:50:17.8053638Z ##[endgroup]
2026-09-28T03:50:17.9194969Z cspell-action
2026-09-28T03:50:17.9204275Z Push
2026-09-28T03:50:18.3527072Z ##[error]Error: Command failed: git diff-tree --no-commit-id --name-only -r 3c9f618d418286eac68aef56857b9559237592b2 7aaad27bcd874b52df2965c6d3c8d15caa934835
fatal: bad object 3c9f618d418286eac68aef56857b9559237592b2

2026-09-28T03:50:18.3604871Z Files checked: 0, Issues found: 0 in 0 files.
2026-09-28T03:50:18.3612049Z Done.