chore: Remove OpenAICompletion

[ranadeepsingh]

Related Issues/PRs

#xxx

What changes are proposed in this pull request?

None of the latest models support the OpenAI Completions API which ended support on July 2023.
Removing all use of OpenAICompletions

How is this patch tested?

• I have written tests (not required for typo or doc fix) and confirmed the proposed feature/bug-fix/change works.

Does this PR change any dependencies?

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• Yes. Make sure the dependencies are resolved correctly, and list changes here.

Does this PR add a new feature? If so, have you added samples on website?

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• Yes. Make sure you have added samples following below steps.

1. Find the corresponding markdown file for your new feature in website/docs/documentation folder.
   Make sure you choose the correct class estimators/transformers and namespace.
2. Follow the pattern in markdown file and add another section for your new API, including pyspark, scala (and .NET potentially) samples.
3. Make sure the DocTable points to correct API link.
4. Navigate to website folder, and run yarn run start to make sure the website renders correctly.
5. Don't forget to add <!--pytest-codeblocks:cont--> before each python code blocks to enable auto-tests for python samples.
6. Make sure the WebsiteSamplesTests job pass in the pipeline.

[github-actions]

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[ranadeepsingh]

/azp run

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[Copilot]

Pull Request Overview

This PR removes the deprecated OpenAICompletion class and all associated code, as the OpenAI Completions API ended support in July 2023 and is no longer supported by current models.

• Removed the OpenAICompletion class and its test suite
• Removed the HasPromptInputs trait which was only used by OpenAICompletion
• Simplified OpenAIPrompt by removing legacy model handling and streamlining service configuration

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

File	Description
cognitive/src/main/scala/com/microsoft/azure/synapse/ml/services/openai/OpenAICompletion.scala	Complete removal of the deprecated OpenAICompletion class
cognitive/src/test/scala/com/microsoft/azure/synapse/ml/services/openai/OpenAICompletionSuite.scala	Removal of test suite for OpenAICompletion
cognitive/src/main/scala/com/microsoft/azure/synapse/ml/services/openai/OpenAI.scala	Removed HasPromptInputs trait that was only used by OpenAICompletion
cognitive/src/main/scala/com/microsoft/azure/synapse/ml/services/openai/OpenAIPrompt.scala	Removed legacy model detection, simplified service configuration to only handle chat-based services, removed unused import, and updated parameter documentation

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 83.33333% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 84.43%. Comparing base (b979064) to head (917e86c).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...zure/synapse/ml/services/openai/OpenAIPrompt.scala	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2447      +/-   ##
==========================================
+ Coverage   84.35%   84.43%   +0.07%     
==========================================
  Files         335      334       -1     
  Lines       17729    17695      -34     
  Branches     1621     1618       -3     
==========================================
- Hits        14955    14940      -15     
+ Misses       2774     2755      -19     

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[BrendanWalsh]

I think we should sunset this (i.e. not spend time keeping it up to date with new features) but not remove it until openai stops serving the endpoint. Thoughts?

[ranadeepsingh]

/azp run

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[ranadeepsingh]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).

[ranadeepsingh]

/azp run

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Azure Pipelines successfully started running 1 pipeline(s).