Fix typo in docs

[TheodoreEhrenborg]

Checklist

If applicable:

• I have updated CHANGELOG.md
• I have updated the documentation (README.md, docs/, demos/)
• I have updated the config schema (cli/src/config-schema.json)
• I have added tests to cover my changes

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[PhilipMetzger]

Thanks for your contribution, but this is not a typo, as it recently was renamed. See 895d53f for the details.

[TheodoreEhrenborg]

Aha, thanks for explaining

In that case, I've just changed file to files in the rest of that section, to match the rename

[PhilipMetzger]

If you can rewrite the commit description with docs: fix typo , I'll land it for you. See https://github.com/martinvonz/jj/blob/main/docs/contributing.md#code-reviews where I mean this part:

The commit message should describe the changes in the commit; the PR description can even be empty, but feel free to include a personal message. We write commit messages in an affected component style and don't use conventional commits. This means if you modified a command in the CLI, use its name as the topic, e.g next/prev: <your-modification> or conflicts: <your-modification>.

[martinvonz]

If you can rewrite the commit description with docs: fix typo

I almost asked to update the description to be clearer but I didn't care enough. Since you're asking for an update anyway, I might as well. Can you make it docs: update stale references to singular file() revset or something like that? Thanks.

[PhilipMetzger]

Thanks again.