Bump chessground from 9.0.5 to 9.1.0

Bumps [chessground](https://github.com/lichess-org/chessground) from 9.0.5 to 9.1.0.
- [Commits](lichess-org/chessground@v9.0.5...v9.1.0)

---
updated-dependencies:
- dependency-name: chessground
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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