Add descriptive alt text for ChatOps

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What does this MR do and why?

This change updates the image alt text in debugging_end_to_end_test_failures.md to replace a filename-only placeholder with a clear, descriptive alternative. The new alt text provides meaningful context about the image content while retaining the original filename token for reference.

This improves accessibility and documentation clarity by ensuring that images convey relevant information to readers using assistive technologies.

References

#479161

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