Use new CircleCI image

Author: kigster

.circleci/Dockerfile

@@ -92,7 +92,7 @@ RUN apt-get update && apt-get upgrade
 
 RUN apt-get install -y openjdk-11-jdk python2.7 python3 golang-go
 
-RUN curl -L -o /usr/bin/bazel https://github.com/bazelbuild/bazelisk/releases/download/v1.3.0/bazelisk-linux-amd64 \
+RUN curl -L -o /usr/bin/bazel https://github.com/bazelbuild/bazelisk/releases/download/v1.12.0/bazelisk-linux-amd64 \
     && sudo chmod +x /usr/bin/bazel
 
 RUN cd /usr/bin && ln -s python3 python

.circleci/README.md

@@ -0,0 +1,14 @@
+## `build.sh`
+
+Anytime you change the Ruby version you must push a new image to Docker Hub.
+
+Email kigster@gmail.com to be added to bazelruby org on hub.docker.com.
+
+### To Upgrade
+
+Change the ruby version in the `Dockerfile` and run:
+
+```bash
+cd .circleci
+./build.sh
+```

.circleci/build.sh

@@ -12,7 +12,7 @@ echo
 
 set -x 
 
-docker build . -t bazelruby/ruby-$RUBY_VERSION
+docker build --platform linux/x86_64 . -t bazelruby/ruby-$RUBY_VERSION
 
 docker push       bazelruby/ruby-$RUBY_VERSION