[@azure/search-documents] Code Changes for Search Release 11.3.0

[sarangan12]

Packages impacted by this PR

@azure/search-documents

Issues associated with this PR

N/A

Describe the problem that is addressed by this PR

We have released the @azure/search-documents SDK V 11.2.1 on August 2021. Now, the request has come to release 11.3.0. But, only 3 features must be included for this release:

1. TokenCredential AAD Support
2. National Cloud Support
3. Any Bug Fixes that went in after August 2021

What are the possible designs available to address the problem? If there are more than one possible design, why was the one in this PR chosen?

So, I have branched off from the 11.2.1 code base and added the appropriate changes. This does not include any regenration or swagger changes.

Are there test cases added in this PR? (If not, why?)

Wherever appropriate, I have modified the test cases to include changes.

Provide a list of related PRs (if any)

None

Checklists

• [X ] Added impacted package name to the issue description
• [ ] Does this PR needs any fixes in the SDK Generator?** (If so, create an Issue in the Autorest/typescript repository and link it here)
• [X] Added a changelog (if necessary)

@xirzec @ShivangiReja Please review and approve the PR.