[Search] Enable semantic_text feature in es3

[saarikabhasi]

Summary

Semantic text feature was disabled by default due to ML node unable to scale down. With the relevant PR & subsequent fix merged, ML node now auto scales when there is no activity. Therefore enabling semantic_text feature in es3.

Testing instructions

• start serverless instance
• visit index management index details page -> mappings
• Click Add field
• Confirm semantic_text is shown in the field type form

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: d76d8b9

Metrics [docs]

✅ unchanged

[TattdCodeMonkey]

@saarikabhasi @sphilipse Do we have FTR tests in place for semantic text in serverless? I would have expected them to be enabled with this change.

If not do we have an issue for adding them? I assume we have them in stack and we need to ensure they are added to our suite. or they may require some additional work to ensure they are available on the expected page(s).

[saarikabhasi]

@TattdCodeMonkey From what I know we don't have FTR for semantic_text yet for serverless & stack. We had this ticket created a while back to have FTRs for serverless & stack and I am not sure if we got around working this. @sphilipse please correct me if I'm wrong

but we do have good amount of unit tests for adding a new semantic_text . Would it okay if we add FTR in an another PR or do we want them in this PR ?

[sphilipse]

No FTRs specifically for semantic text, no. That's still an open issue.

[TattdCodeMonkey]

Would it okay if we add FTR in an another PR or do we want them in this PR ?

I think it's ok that we add FTR with another PR(s), I just wanted to call it out that we know we're doing that in this case.

[kc13greiner]

LGTM!