Python: Add OpenAI's sequence_number attribute to unit tests based on their latest package (#12227)

### Motivation and Context

OpenAI release a new python package (1.81.0) which has some updates to
the underlying Pydantic models for the Responses API. We need to pull in
a new change for `ResponseOutputItemDoneEvent`,
`ResponseOutputItemAddedEvent`, and `ResponseTextDeltaEvent` for
streaming invocation which now has `sequence_number` attribute.

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### Description

Bring in a change from OpenAI's Python SDK from v1.81.0 related to SK's
OpenAIResponsesAgent.

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### Contribution Checklist

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- [X] The code builds clean without any errors or warnings
- [X] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [X] All unit tests pass, and I have added new tests where possible
- [X] I didn't break anyone 😄

Author: moonbox3

python/tests/unit/agents/openai_responses/test_openai_responses_thread_actions.py

@@ -252,6 +252,7 @@ async def __anext__(self):
         item_id="fake-item-id",
         output_index=0,
         type="response.output_text.delta",
+        sequence_number=0,
     )
 
     mock_stream_event_end = ResponseOutputItemDoneEvent(
@@ -263,6 +264,7 @@ async def __anext__(self):
             type="message",
         ),
         output_index=0,
+        sequence_number=0,
         type="response.output_item.done",
     )
 
@@ -321,6 +323,7 @@ async def __anext__(self):
         ),
         output_index=0,
         type="response.output_item.added",
+        sequence_number=0,
     )
 
     mock_stream_event_end = ResponseOutputItemDoneEvent(
@@ -332,6 +335,7 @@ async def __anext__(self):
             type="message",
         ),
         output_index=0,
+        sequence_number=0,
         type="response.output_item.done",
     )