Fix UnboundLocalError in create_finetuning_job when validation_data is None

[saanikaguptamicrosoft]

Notes

• Fix UnboundLocalError in create_finetuning_job when validation_data is None: [BUG] create_finetuning_job() crashes with UnboundLocalError when validation_data is None (optional per signature) #45770
• Added the missing UT

Testing

1. Via repro script

• Before changes

- After changes

2. Samples testing - SDK Samples Run generated from 6072125 azureml-examples#3840

• Compared with samples run against main: SDK Samples Run generated from 6072250 azureml-examples#3841

4. Unit tests ~ Successful

Description

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• The pull request does not introduce [breaking changes]
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[Copilot]

Pull request overview

Fixes a crash in azure-ai-ml fine-tuning job creation when validation_data is omitted (None), and adds a unit test to prevent regression.

Changes:

• Update create_finetuning_job to pass None for validation_data when it isn’t provided, avoiding an UnboundLocalError.
• Add a unit test validating create_finetuning_job works when validation_data is omitted.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
sdk/ml/azure-ai-ml/azure/ai/ml/finetuning/_create_job.py	Prevents UnboundLocalError by conditionally passing None for validation_data.
sdk/ml/azure-ai-ml/tests/finetuning_job/unittests/test_finetuning_job_convesion.py	Adds regression coverage for validation_data=None behavior.