Abstract 6.3 changes into a separate task to reduce all of the jinja one

liner complexity

Set ES_PATH_CONF when installing so upgrading from 6.2 to 6.3 works as
expected

tasks/elasticsearch-RedHat.yml

@@ -25,6 +25,8 @@
   until: redhat_elasticsearch_install_from_repo.rc == 0
   retries: 5
   delay: 10
+  environment:
+    ES_PATH_CONF: "/etc/elasticsearch"
 
 - name: RedHat - Install Elasticsearch from url
   become: yes