Add support for OpenAI batch completions API

[kowshik24]

Fixes #1689

Add support for OpenAI's batch completions API.

• Instrumentation: Update packages/opentelemetry-instrumentation-openai/opentelemetry/instrumentation/openai/__init__.py to add support for batch completions in the OpenAIInstrumentor class. Import necessary modules and wrap the create_batch methods for both synchronous and asynchronous completions.
• Completion Wrappers: Update packages/opentelemetry-instrumentation-openai/opentelemetry/instrumentation/openai/shared/completion_wrappers.py to add new wrapper functions for batch completions. Handle request and response attributes for batch completions.
• Tests: Add tests for batch completions in packages/opentelemetry-instrumentation-openai/tests/traces/test_completions.py. Include tests for both synchronous and asynchronous batch completions. Verify span attributes and response handling.

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For more details, open the Copilot Workspace session.

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[!IMPORTANT] Add support for OpenAI batch completions API with instrumentation, completion wrappers, and tests.

• Instrumentation:
  • Update __init__.py to support batch completions in OpenAIInstrumentor.
  • Wrap create_batch methods for sync and async completions.
• Completion Wrappers:
  • Add batch_completion_wrapper and abatch_completion_wrapper in completion_wrappers.py.
  • Handle request and response attributes for batch completions.
• Tests:
  • Add tests for batch completions in test_completions.py.
  • Include tests for sync and async batch completions, verifying span attributes and response handling.

^{This description was created by for a01cf0b1d753586ac93a05084c53ac129aac363f. It will automatically update as commits are pushed.}

[kowshik24]

@nirga I have made the changes could you please take a look?

[kowshik24]

@nirga Please take a look I have added the tests

[nirga]

@kowshik24 checking if you're still working on this?