Bump js-yaml from 4.1.1 to 4.3.1 in /src/redocly-plugins

Bumps [js-yaml](https://github.com/nodeca/js-yaml) from 4.1.1 to 4.3.1.
- [Changelog](https://github.com/nodeca/js-yaml/blob/4.3.1/CHANGELOG.md)
- [Commits](https://github.com/nodeca/js-yaml/compare/4.1.1...4.3.1)

---
updated-dependencies:
- dependency-name: js-yaml
  dependency-version: 4.3.1
  dependency-type: indirect
...

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