feature/unit-test-irs-batch-response

[ds-vlisenco]

Description
test: add unit tests for IrsBatchResponse and nested JobRecord class

This PR introduces unit tests for the IrsBatchResponse class and its nested static class JobRecord.
These tests improve code coverage and ensure that the data structures behave as expected under typical and edge-case conditions.

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Changes

• Added unit tests for:
  • Standard constructor and accessors of IrsBatchResponse and JobRecord
  • Behavior with null values
  • Behavior with an empty jobs list
  • Validation of accessors for JobRecord
• Edge case covered:
  • All optional or nullable fields set to null or default values
  • Ensures null-safety and resilience when handling incomplete or corrupted data

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Notes

• No related issue
• Helps verify system robustness in edge scenarios
• Aligned with project coding standards

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Pre-review checks
☑ DEPENDENCIES are up-to-date
☑ Copyright and license header
☑ Tests added and passing
☑ Code formatting and structure checked