Fail when test results cannot be published

[dibarbet]

Summary

• fail the shared xUnit publishing task when Azure Pipelines cannot publish all test results
• fail the task when no test result files are produced
• surface incomplete test reporting as a task failure instead of a warning

This prevents runs such as 20260825.36 from showing only the test script failure when the test-results service rejects part of the upload. Log and dump publication remains unaffected because those steps use condition: always().

Validation

• verified PublishTestResults@2 supports both failure options
• ran git diff --check

[azure-pipelines]

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[Copilot]

Pull request overview

This PR tightens Azure Pipelines behavior in Roslyn’s shared log/test publishing template so that failures to publish test results are treated as task failures (rather than warnings), improving signal when the test-results service rejects uploads.

Changes:

• Configure the PublishTestResults@2 xUnit publishing step to fail if Azure Pipelines cannot publish all test results.

Show a summary per file

File	Description
eng/pipelines/publish-logs.yml	Makes xUnit test-result publication failures fail the publishing task via failTaskOnFailureToPublishResults: true.

Review details

• Files reviewed: 1/1 changed files
• Comments generated: 0
• Review effort level: Lite

[Copilot]

Review details

• Files reviewed: 1/1 changed files
• Comments generated: 0 new
• Review effort level: Lite