Merge pull request #495 from jhuttana/add_guard_check

[OPENJDK-2894] Add a guard check in Dockerfile for presence of jlink scripts

Author: jmtd

templates/jlink/jlinked-app.yaml

@@ -51,6 +51,7 @@ objects:
     source:
       dockerfile: |
         FROM -
+        RUN if [ ! -f "/opt/jboss/container/java/jlink/preflight.sh" ]; then echo "jlink scripts doesn't exist" 2>&1; exit 1; fi
         USER 0
         RUN microdnf --setopt=install_weak_deps=0 --setopt=tsflags=nodocs install -y java-${JDK_VERSION}-openjdk-jmods
         RUN mkdir -p /mnt/jrootfs