.Net: Add Azure CosmosDB NoSQL Hybrid Keyword Search

[westey-m]

Motivation and Context

#9399

Description

• Add an azure ComsosDB NoSQL hybrid search implementation using keywords
• Add integration tests and update unit tests.
• The required features to implement this is only available in preview versions of the SDK right now.

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the SK Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄