Fixes and improvements needed in authoring-ha and managed

While working on RHDM-721 and RHPAM-1488, various issues and certain improvements were discovered/missing in the elasticsearch authoring-ha templates and code and fixed there:

• fix to amq scaledown controller image stream tag
• adding missing service references, session affinity, and dns ping sections
• add ability to lookup elasticsearch host and port by service name
• cleanup of annotations, labels, and yaml descriptions
• maven mirror url missing in rhpam managed template

However, because those datagrid jiras might be moving to 7.3.1 or 7.3.0, this jira has been created to at least address those issues for 7.3.0.