[AI assistant]: Document support for Claude 3 models

[dedemorton]

Description

Support for Claude 3 models is being added to the Obs AI Assistant. We need to update the docs accordingly and remove the sentence that says, "Note that we do not currently support Claude 3.0 models.”

Resources

elastic/kibana#179304

Which documentation set does this change impact?

Stateful and Serverless

Feature differences

The feature is identical in stateful and serverless.

What release is this request related to?

8.14

Collaboration model

The documentation team

Point of contact.

Main contact: @DarioG

Stakeholders:

[dedemorton]

I'm moving this to Sprint 20 because the code was merged a few weeks ago and is probably in serverless already (need to check).