Upgrade OpenJDK8 to latest available version (#985)

environments/jvm/builder/Dockerfile

@@ -2,7 +2,7 @@
 ARG BUILDER_IMAGE=fission/builder:latest
 FROM ${BUILDER_IMAGE}
 
-## Section copied from the OpenJDK 8 Dockerfile
+## Section copied from the openjdk:8-jdk-alpine Dockerfile - (https://github.com/docker-library/openjdk/blob/47a6539cd18023dafb45db9013455136cc0bca07/8/jdk/alpine/Dockerfile)
 
 ENV LANG C.UTF-8
 RUN { \
@@ -15,8 +15,8 @@ RUN { \
 ENV JAVA_HOME /usr/lib/jvm/java-1.8-openjdk
 ENV PATH $PATH:/usr/lib/jvm/java-1.8-openjdk/jre/bin:/usr/lib/jvm/java-1.8-openjdk/bin
 
-ENV JAVA_VERSION 8u171
-ENV JAVA_ALPINE_VERSION 8.171.11-r0
+ENV JAVA_VERSION 8u181
+ENV JAVA_ALPINE_VERSION 8.181.13-r0
 
 RUN set -x \
     && apk add --no-cache \