Bump protobufjs from 7.5.5 to 7.5.8 in /extensions/copilot (#316074)

Bumps [protobufjs](https://github.com/protobufjs/protobuf.js) from 7.5.5 to 7.5.8.
- [Release notes](https://github.com/protobufjs/protobuf.js/releases)
- [Changelog](https://github.com/protobufjs/protobuf.js/blob/protobufjs-v7.5.8/CHANGELOG.md)
- [Commits](https://github.com/protobufjs/protobuf.js/compare/protobufjs-v7.5.5...protobufjs-v7.5.8)

---
updated-dependencies:
- dependency-name: protobufjs
  dependency-version: 7.5.8
  dependency-type: indirect
...

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