Fix debian9 docker file and clean up centos8 and ubuntu18.04 (#3518)

Author: nwangtw

docker/base/Dockerfile.base.debian9

@@ -15,7 +15,7 @@
 #  specific language governing permissions and limitations
 #  under the License.
 
-FROM openjdk:8-jdk-slim
+FROM openjdk:11-jdk-slim-stretch
 
 RUN apt-get -y update && apt-get -y install \
     netcat-openbsd \

docker/test/Dockerfile.centos7

@@ -19,7 +19,7 @@ FROM centos:centos7
 
 # This is passed to the heron build command via the --config flag
 ENV TARGET_PLATFORM centos
-ENV bazelVersion 0.26.0
+ENV bazelVersion 3.0.0
 
 RUN yum -y upgrade
 RUN yum -y install \
@@ -33,6 +33,7 @@ RUN yum -y install \
       git \
       kernel-devel \
       libtool \
+      cppunit-devel \
       make \
       patch \
       python-devel \

docker/test/Dockerfile.ubuntu18.04

@@ -19,14 +19,15 @@ FROM ubuntu:18.04
 
 # This is passed to the heron build command via the --config flag
 ENV TARGET_PLATFORM ubuntu
-ENV bazelVersion 0.26.0
+ENV bazelVersion 3.0.0
 
 RUN apt-get update && apt-get -y install \
       g++ \
       cmake \
       automake \
       libtool-bin \
       libunwind8 \
+      libcppunit-dev \
       patch \
       python-dev \
       python3-dev \