Graduate AzureAISearch feature

[markwallace-microsoft]

Feature graduation planning for AzureAISearch

• Azure.Search.Documents 11.6.0 GA package is available
• Declare GA on what we have
• Switch back to Beta to match the 11.7.0 package

Checklist to be completed when graduating an experimental feature

• [ ] Notify PM's and EM's that feature is ready for graduation
• [ ] Contact PM for list of sample use cases
• [ ] Verify there are sample implementations​ for each of the use cases
• [ ] Verify telemetry and logging are complete
• [ ] ​Verify API docs are complete and arrange to have them published
• [ ] Make appropriate updates to Learn docs​
• [ ] Make appropriate updates to Concept samples
• [ ] Make appropriate updates to Blog posts
• [ ] Verify there are no serious open Issues​​
• [ ] Update table in EXPERIMENTS.md
• [ ] Remove SKEXP​ flag from the experimental code