bump protoc version in build, use newer syntax in .proto

Dockerfile

@@ -13,7 +13,12 @@ FROM golang@sha256:52a48e0239f4d645b20ac268a60361703afe7feb2df5697fa89f72052cb87
 #FROM golang:1.16-buster AS builder
 
 ENV DEBIAN_FRONTEND noninteractive
-RUN apt update && apt install -y make bzip2 protobuf-compiler
+RUN apt update && apt install -y make bzip2 curl unzip
+
+# install newer protoc than what comes with buster
+ENV PB_REL https://github.com/protocolbuffers/protobuf/releases
+RUN curl -LO $PB_REL/download/v3.19.0/protoc-3.19.0-linux-x86_64.zip && \
+    unzip protoc-3.19.0-linux-x86_64.zip -d /usr/local
 
 RUN mkdir -p /build
 WORKDIR /build
@@ -26,7 +31,7 @@ COPY ./ ./
 # image and we already did it in a previous stage
 #RUN make lint
 RUN make mfer
-RUN go mod vendor
+#RUN go mod vendor
 RUN tar -c . | bzip2 > /src.tbz2