Bing grounding citations

[abdomohamed]

Adding support for Bing grounding citations to the AzureAIAgent.

Why are these changes needed?

Related issue number

Checks

• I've included any doc changes needed for https://microsoft.github.io/autogen/. See https://github.com/microsoft/autogen/blob/main/CONTRIBUTING.md to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.

[codecov]

Codecov Report

Attention: Patch coverage is 94.87179% with 2 lines in your changes missing coverage. Please review.

Project coverage is 75.68%. Comparing base (998840f) to head (8f0e6ad).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...xt/src/autogen_ext/agents/azure/_azure_ai_agent.py	97.22%	1 Missing ⚠️
...autogen-ext/src/autogen_ext/agents/azure/_types.py	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6370      +/-   ##
==========================================
- Coverage   78.26%   75.68%   -2.58%     
==========================================
  Files         221      182      -39     
  Lines       16158    13225    -2933     
==========================================
- Hits        12646    10010    -2636     
+ Misses       3512     3215     -297     

Flag	Coverage Δ
unittests	75.68% <94.87%> (-2.58%)	⬇️

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