Replace generic AirflowException in AzureBatchOperator input validation

[baha-bouali]

Follow-up to #71071

CONTEXT: get the operators/batch.py entry in generated/known_airflow_exceptions.txt removed entirely.

What changed

AzureBatchOperator._check_inputs() had 8 bare raise AirflowException(...) calls. Each now raises a specific exception instead, defined in a new providers/microsoft/azure/exceptions.py:

Condition	Exception
vm_publisher not provided	AzureBatchVmPublisherMissingError
use_latest_verified_vm_image_and_sku without a complete image spec	AzureBatchLatestImageSpecIncompleteError
vm_publisher without vm_sku/vm_offer/vm_node_agent_sku_id	AzureBatchVmImageSpecIncompleteError
Neither target_dedicated_nodes nor enable_auto_scale	AzureBatchPoolSizingMissingError
enable_auto_scale combined with explicit node counts	AzureBatchPoolSizingConflictError
enable_auto_scale without auto_scale_formula	AzureBatchAutoScaleFormulaMissingError
batch_job_release_task without batch_job_preparation_task	AzureBatchJobPreparationTaskMissingError
Required pool/job/task parameters missing	AzureBatchRequiredParametersMissingError

All 8 subclass AirflowException, so existing except AirflowException handling around this operator is unaffected. Message strings are unchanged — only the exception types differ.

The allowlist entry is now gone rather than reduced: the checker deletes the line when the count reaches 0.

Testing

• New tests/unit/microsoft/azure/test_exceptions.py: 24 cases covering inheritance, raising, and catchability as AirflowException.
• operators/test_batch.py: the 19 existing tests passed unmodified after the change, confirming base-class compatibility. They're now tightened to assert the specific exception, and 4 previously untested validation branches have coverage: 23 tests total.

Was generative AI tooling used to co-author this PR?

• Yes
• Assited by Claude Sonnet 5. Reviewed, written and tested by the submitter