Update yard

[ksss]

• Bundle update.
• move _generators under yard/0.9. Because _generators is easily confused with version names.
• Support new testing system on gem_rbs_collection.
• Update few signature.

[github-actions]

@ksss Thanks for your contribution!

Please follow the instructions below for each change.
See also: https://github.com/ruby/gem_rbs_collection/blob/main/docs/CONTRIBUTING.md

Available commands

You can use the following commands by commenting on this PR.

• /merge: Merge this PR if CI passes

---

yard

You changed RBS files for an existing gem.
You can merge this PR yourself because you are a reviewer of this gem.
Just comment /merge to merge this PR.

You can also request a review from other reviewers if you want.

[ksss]

/merge