Trim un-necessary steps from Dockerfile

(cherry picked from commit b6a129470f69050922918c4a205c9e9dd26df901)

Author: matrober-uk

openshift-app-sample/Dockerfile

@@ -1,5 +1,4 @@
  FROM golang:1.15 as builder
- ENV APP_USER app
  ENV APP_HOME /go/src/openshift-app-sample
  RUN mkdir -p /opt/mqm \
    && chmod a+rx /opt/mqm
@@ -18,25 +17,20 @@
    && tar -zxf ./*.tar.gz \
    && rm -f ./*.tar.gz \
    && bin/genmqpkg.sh -b /opt/mqm
- RUN groupadd $APP_USER && useradd -m -g $APP_USER -l $APP_USER
- RUN mkdir -p $APP_HOME && chown -R $APP_USER:$APP_USER $APP_HOME
+ RUN mkdir -p $APP_HOME
  WORKDIR $APP_HOME
- USER $APP_USER
  COPY src/ .
  RUN go build -o openshift-app-sample
 
  FROM golang:1.15
- ENV APP_USER app
  ENV APP_HOME /go/src/openshift-app-sample
- RUN groupadd $APP_USER && useradd -m -g $APP_USER -l $APP_USER
- RUN mkdir -p $APP_HOME
  # Create the directories the client expects to be present
- RUN mkdir -p /IBM/MQ/data/errors \
+ RUN mkdir -p $APP_HOME \
+   && mkdir -p /IBM/MQ/data/errors \
    && mkdir -p /.mqm \
    && chmod -R 777 /IBM \
    && chmod -R 777 /.mqm
  WORKDIR $APP_HOME
  COPY --chown=0:0 --from=builder $APP_HOME/openshift-app-sample $APP_HOME
  COPY --chown=0:0 --from=builder /opt/mqm /opt/mqm
- USER $APP_USER
  CMD ["./openshift-app-sample"]

openshift-app-sample/yaml/pod-sample.yaml

@@ -5,7 +5,7 @@ metadata:
 spec:
   containers:
     - name: golang-app
-      image: uk.icr.io/golang-sample/golang-app:1.6
+      image: uk.icr.io/golang-sample/golang-app:1.0
       envFrom:
       - configMapRef:
           name: qmgr-details