Bump google.golang.org/grpc from 1.54.0 to 1.56.3 in /src/operator

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.54.0 to 1.56.3.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](grpc/grpc-go@v1.54.0...v1.56.3)

---
updated-dependencies:
- dependency-name: google.golang.org/grpc
  dependency-type: direct:production
...

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