chore: Ensure consistent version of generate proto stubs (#58)

Ensure the versions of the generated protobuf code stubs are consistent
with the versions as specified in the Dockerfile and the go.mo file.

- protoc             v3.21.5
- protoc-gen-go      v1.28.1
- protoc-gen-go-grpc v1.3.0

Signed-off-by: Christian Kadner <[email protected]>

Author: ckadner

Dockerfile

@@ -77,9 +77,13 @@ WORKDIR /opt/app
 COPY go.mod go.sum ./
 
 # Install go protoc plugins
+# no required module provides package google.golang.org/grpc/cmd/protoc-gen-go-grpc
+# to add it run `go get google.golang.org/grpc/cmd/protoc-gen-go-grpc`
 ENV PATH $HOME/go/bin:$PATH
-RUN go get google.golang.org/protobuf/cmd/protoc-gen-go \
-           google.golang.org/grpc/cmd/protoc-gen-go-grpc \
+RUN true \
+    && go get google.golang.org/grpc/cmd/protoc-gen-go-grpc \
+    && go install google.golang.org/protobuf/cmd/protoc-gen-go \
+                  google.golang.org/grpc/cmd/protoc-gen-go-grpc \
     && protoc-gen-go --version \
     && true