Bump protobufjs, @grpc/proto-loader and @grpc/grpc-js in /examples/node

Bumps [protobufjs](https://github.com/protobufjs/protobuf.js) to 7.5.5 and updates ancestor dependencies [protobufjs](https://github.com/protobufjs/protobuf.js), [@grpc/proto-loader](https://github.com/grpc/grpc-node) and [@grpc/grpc-js](https://github.com/grpc/grpc-node). These dependencies need to be updated together.


Updates `protobufjs` from 6.10.1 to 7.5.5
- [Release notes](https://github.com/protobufjs/protobuf.js/releases)
- [Changelog](https://github.com/protobufjs/protobuf.js/blob/master/CHANGELOG.md)
- [Commits](protobufjs/protobuf.js@v6.10.1...protobufjs-v7.5.5)

Updates `@grpc/proto-loader` from 0.5.5 to 0.8.0
- [Release notes](https://github.com/grpc/grpc-node/releases)
- [Commits](https://github.com/grpc/grpc-node/commits/@grpc/proto-loader@0.8.0)

Updates `@grpc/grpc-js` from 1.1.8 to 1.14.3
- [Release notes](https://github.com/grpc/grpc-node/releases)
- [Commits](https://github.com/grpc/grpc-node/commits/@grpc/grpc-js@1.14.3)

---
updated-dependencies:
- dependency-name: protobufjs
  dependency-version: 7.5.5
  dependency-type: indirect
- dependency-name: "@grpc/proto-loader"
  dependency-version: 0.8.0
  dependency-type: direct:production
- dependency-name: "@grpc/grpc-js"
  dependency-version: 1.14.3
  dependency-type: direct:production
...

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Author: dependabot[bot]