Get Ingest Management docs building

[dedemorton]

Initial PR to add ingest management docs.

Draft until we get the initial files in place.

Open issues:

• Finalize location of the content. The options are:
  • Put under Elastic Stack
  • Put under Observability: APM, Logs, Metrics, and Uptime
  • Rename "Beats: Collect, Parse, and Ship" to "Collect, Parse, and Ship" and put under there.

UPDATE: Decision was to put under Beats for now because this feature is experimental.

[gtback]

This is fine with me.

At some point I'd like to talk about whether it makes sense to have multiple branches of some of the solution docs, though maybe that applies more to Observability as a whole rather than the Ingest Management guide. I think for product reference, building multiple branches makes a lot of sense, but I'm not as sure about this type of guide.

[gtback]

CI is failing because stackcurrent (i.e. 7.7) is not in the list of branches getting built.

[dedemorton]

CI is failing because stackcurrent (i.e. 7.7) is not in the list of branches getting built.

Fixed! The build might fail again because we don't have all the asciidoc source files properly merged yet.

[dedemorton]

@elasticmachine run elasticsearch-ci/docs

[dedemorton]

@elasticmachine run elasticsearch-ci/docs

[dedemorton]

@elasticmachine run elasticsearch-ci/docs