add update-grpc to Makefile to generate grpc proto files

Makefile

@@ -19,6 +19,14 @@ build-arm:
 	# Build binary for ARM architecture (aarch64)
 	./util/build_arm.sh
 
+update-grpc:
+	go get -u github.com/golang/protobuf/proto
+	go get -u github.com/golang/protobuf/protoc-gen-go
+	go get -u google.golang.org/grpc
+	cd walletrpc && protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative service.proto
+	cd walletrpc && protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative compact_formats.proto
+	go mod tidy && go mod vendor
+
 # Stop the hushd process in the hushdlwd container
 #docker_img_stop_hushd:
 #	docker exec -i hushdlwd hush-cli stop