Bump fast-uri from 3.1.2 to 3.1.6 in /src/redocly-plugins

Bumps [fast-uri](https://github.com/fastify/fast-uri) from 3.1.2 to 3.1.6.
- [Release notes](https://github.com/fastify/fast-uri/releases)
- [Commits](https://github.com/fastify/fast-uri/compare/v3.1.2...v3.1.6)

---
updated-dependencies:
- dependency-name: fast-uri
  dependency-version: 3.1.6
  dependency-type: indirect
...

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