[18.0][FIX] odoo_repository: GitPython 3.1.59 compatibility

[lmignon]

GitPython 3.1.59, released on 2026-08-10, added '--separate-git-dir' to the list of unsafe options.

Allow unsafe options on clone created with workaround_fs_errors=True since they are the only once using this option.

Without this fix tests for `workaround_fs_error=Truer fails

[7](https://github.com/OCA/module-composition-analysis/actions/runs/31675398000/job/94368767381?pr=157#step:8:328)
2026-08-13 06:52:41,227 312 ERROR odoo odoo.addons.odoo_repository.tests.test_repository_scanner: ERROR: TestRepositoryScanner.test_workaround_fs_errors
Traceback (most recent call last):
  File "/__w/module-composition-analysis/module-composition-analysis/odoo_repository/tests/test_repository_scanner.py", line 215, in test_workaround_fs_errors
    scanner.sync()
  File "/__w/module-composition-analysis/module-composition-analysis/odoo_repository/lib/scanner.py", line 108, in sync
    res = self._clone()
  File "/__w/module-composition-analysis/module-composition-analysis/odoo_repository/lib/scanner.py", line 252, in _clone
    git.Repo.clone_from(**params)
  File "/opt/odoo-venv/lib/python3.10/site-packages/git/repo/base.py", line 1676, in clone_from
    return cls._clone(
  File "/opt/odoo-venv/lib/python3.10/site-packages/git/repo/base.py", line 1515, in _clone
    Git.check_unsafe_options(
  File "/opt/odoo-venv/lib/python3.10/site-packages/git/cmd.py", line 1025, in check_unsafe_options
    raise UnsafeOptionError(f"{unsafe_option} is not allowed, use `allow_unsafe_options=True` to allow it.")
git.exc.UnsafeOptionError: --separate-git-dir is not allowed, use `allow_unsafe_options=True` to allow it.

[sebalix]

Thank you!
I'm not using anymore workaround_fs_errors option, but it was kind of required with mounted volumes on Azure. I would prefer to drop all of this workaround one day as it wasn't addressing all encountered issues anyway (like updating git remotes in existing repositories to compare commits between repositories). Better to keep it for now I guess.

Do you need it in your deployment?

[sebalix]

Merging as it's blocking others PRs

/ocabot merge patch

[OCA-git-bot]

What a great day to merge this nice PR. Let's do it!
Prepared branch 18.0-ocabot-merge-pr-158-by-sebalix-bump-patch, awaiting test results.

[OCA-git-bot]

Congratulations, your PR was merged at c814311. Thanks a lot for contributing to OCA. ❤️

[lmignon]

Thank you! I'm not using anymore workaround_fs_errors option, but it was kind of required with mounted volumes on Azure. I would prefer to drop all of this workaround one day as it wasn't addressing all encountered issues anyway (like updating git remotes in existing repositories to compare commits between repositories). Better to keep it for now I guess.

Do you need it in your deployment?

Not at all... (at least AFAIK) but changes required to make the CI 💚 😏