Migrate Protobuf Module

[lmangani]

go: module github.com/golang/protobuf is deprecated: Use the "google.golang.org/protobuf" module instead.

1. Update the Import Paths
   Replace all occurrences of github.com/golang/protobuf with google.golang.org/protobuf
2. Update the Go Modules
   Replace the dependency on github.com/golang/protobuf with google.golang.org/protobuf:
3. Update Code References
   The google.golang.org/protobuf package has some changes compared to github.com/golang/protobuf. For example:

• proto.Message is now an interface, not a struct.
• Methods like proto.Marshal, proto.Unmarshal, and proto.Equal are now in google.golang.org/protobuf/proto.