Upgrade to 4.2.1.2

This document describes how to upgrade to version 4.2.1.2.

In 4.2.1.2, we made volume size for mariadb, elasticsearch, and hbase configurable, so you will have to run the following before running terraform

1118  kubectl delete statefulset/<app_name>-mariadb-primary
1119  kubectl delete statefulset/<app_name>-mariadb-secondary
1122  kubectl delete deployment/<app_name>-hbase-hdfs-httpfs
1126  kubectl delete StatefulSet/<app_name>-hbase-hdfs-datanode
1128  kubectl delete deployment/<app_name>-metricbeat-metricbeat-metrics
1130  kubectl delete statefulset/<app_name>-hbase-hdfs-namenode
1132  kubectl delete statefulset/<app_name>-hbase-zookeeper