simplify some all(all(...)) in combinat and geometry

[fchapoton]

📚 Description

replace some nested all by just one all in combinat and geometry folders

📝 Checklist

• The title is concise, informative, and self-explanatory.
• The description explains in detail what this PR is about.
• I have linked a relevant issue or discussion.
• I have created tests covering the changes.
• I have updated the documentation accordingly.

⌛ Dependencies

[github-actions]

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Built with commit: 0618a28

[dcoudert]

LGTM.

[tscrim]

There are other changes that are not mentioned in the PR description. Are these from a dependency or also done here? If here, some justification is need for changing a # long time to a # not tested. (I also dislike adding spaces in operators enclosed within a [] operator as I think it makes it harder to read; PEP8 allows no spacing.)