docs: Add documentation for deploying with limited Azure OpenAI quota

[Kanchan-Microsoft]

Purpose

This pull request adds a new documentation file to guide users on deploying the Document Knowledge Mining Solution Accelerator when their Azure OpenAI quota is limited. The document explains how to adjust deployment settings to accommodate lower token-per-minute (TPM) limits, outlines configuration steps, and provides performance considerations.

Documentation improvements:

• Added docs/DeployWithLimitedQuota.md to provide step-by-step instructions for deploying with reduced Azure OpenAI quota, including options to bypass or modify quota validation in infra/main.bicep.
• Included guidance on updating environment variables and explained the impact of reduced TPM on application performance.
• Linked to related resources for further information, such as the deployment guide and quota check script.
• Clarified why quota validation is necessary and how to avoid deployment failures due to hardcoded thresholds in the infrastructure file.

Does this introduce a breaking change?

• Yes
• No

Golden Path Validation

• I have tested the primary workflows (the "golden path") to ensure they function correctly without errors.

Deployment Validation

• I have validated the deployment process successfully and all services are running as expected with this change.

What to Check

Verify that the following are valid

• ...

Other Information

[Prajwal-Microsoft]

Recommended option should be on top