Avoid deprecation warnings due to monitoring index templates.

[jtibshirani]

When putting and getting templates, monitoring currently uses the old typed APIs. In particular, the type name is included in the mapping definition, and when communicating over REST, the parameter include_type_name=true is specified.

When we soon deprecate the typed put + get templates calls on master, this will result in us issuing deprecation warnings when the monitoring http exporter is used. This won't be a great experience for users, as they'll receive deprecation warnings that are out of their control to fix. Note that if the http exporter needs to be able to connect to a 6.7 cluster, then include_type_name should be explicitly provided and set to false, since include_type_name defaults to true in 6.7 (whereas on master it defaults to false).

[elasticmachine]

Pinging @elastic/es-core-features

[kesslerm]

The new parameter include_type_name breaks remote monitoring if the remote cluster is still on an older version of Elasticsearch.

[jtibshirani]

@kesslerm I don't think this is a supported configuration. From https://www.elastic.co/guide/en/elastic-stack-overview/current/how-monitoring-works.html:

In general, the monitoring cluster and the clusters being monitored should be running the same version of the stack. A monitoring cluster cannot monitor production clusters running newer versions of the stack.

When deciding how to tackle warnings in monitoring, we relied on this restriction (that the remote cluster must be upgraded first).

[jtibshirani]

Closing this issue, as it was addressed in the linked PRs.