Forward port of backport improvements #4123

[Mpdreamz]

Cherry-pick improvements made as part of the backport of #4123 yaml test runner to 7.x: #4179

[Mpdreamz]

Test failures are due to changes in 8.0.0-SNAPSHOT that our manged elasticsearch need to account for:

[2019-10-29T03:03:56,249][INFO ][Managed Elasticsearch    ]  {Call} [http://localhost:9200/_xpack/license?filter_path=license.type&pretty=true] returned [  "error" : "no handler found for uri [/_xpack/license?filter_path=license.type&pretty=true] and method [GET]"]
[2019-10-29T03:03:56,249][INFO ][Managed Elasticsearch    ]  {Call} [http://localhost:9200/_xpack/license?filter_path=license.type&pretty=true] returned [}]
[2019-10-29T03:03:56,249][INFO ][Managed Elasticsearch    ]  {Call} [http://localhost:9200/_xpack/license?filter_path=license.type&pretty=true] returned []