parametrized Dockerfile and update dev readme.

Dockerfile

@@ -1,7 +1,8 @@
 FROM openjdk:11-jre-slim
 MAINTAINER Alexei Vinogradov
+ARG BROKER_VERSION
 WORKDIR /opt/test-data-broker
-COPY build/libs/test-data-broker-0.2.0.jar .
+COPY build/libs/test-data-broker-$BROKER_VERSION.jar .
 EXPOSE 8080
-ENTRYPOINT ["java", "-jar", "test-data-broker-0.2.0.jar"]
+ENTRYPOINT ["java", "-jar", "test-data-broker-$BROKER_VERSION.jar"]
 

README_DEVELOPER.md

@@ -7,5 +7,7 @@ Security & Signing settings must be in gradle.properties
 
 ## publish docker image for arm64 (mac m1) and amd64 architectures
 
+You might need to create a new driver with eg. `docker buildx create --use` for the first execution.
+
 1. `docker login`
-2. `docker buildx build --platform linux/amd64,linux/arm64 -t vinogradoff/test-data-broker:x.y.z -t vinogradoff/test-data-broker:latest . --push`
+2. `docker buildx build --build-arg BROKER_VERSION=x.y.z --platform linux/amd64,linux/arm64 -t vinogradoff/test-data-broker:x.y.z -t vinogradoff/test-data-broker:latest . --push`