[CI] Add error log in run_tests_with_coverage

[EmmonsCurse]

Motivation

The CI unit test workflow previously only surfaced exit codes when failures occurred, which made troubleshooting slow and inefficient. In many cases, critical server logs were not surfaced, so developers had no visibility into the root cause of failing tests. To improve debuggability, we need to automatically collect and display relevant logs whenever a test fails.

Modifications

• When a pytest execution fails, automatically print related logs (server.log, server_prefill.log, server_decode.log, workerlog.*, etc.).
• Print the last 25 lines of each log to make debugging easier.

Usage or Command

N/A

Accuracy Tests

N/A

Checklist

• [x] Add at least a tag in the PR title.
  • Tag list: [[FDConfig],[APIServer],[Engine], [Scheduler], [PD Disaggregation], [Executor], [Graph Optimization], [Speculative Decoding], [RL], [Models], [Quantization], [Loader], [OP], [KVCache], [DataProcessor], [BugFix], [Docs], [CI], [Optimization], [Feature], [Benchmark], [Others], [XPU], [HPU], [GCU], [DCU], [Iluvatar], [Metax]]
  • You can add new tags based on the PR content, but the semantics must be clear.
• [x] Format your code, run pre-commit before commit.
• [x] Add unit tests. Please write the reason in this PR if no unit tests.
• [x] Provide accuracy results.
• [x] If the current PR is submitting to the release branch, make sure the PR has been submitted to the develop branch, then cherry-pick it to the release branch with the [Cherry-Pick] PR tag.

[codecov-commenter]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :warning: Please upload report for BASE (develop@f88c159). Learn more about missing BASE report.

Additional details and impacted files

@@            Coverage Diff             @@
##             develop    #5370   +/-   ##
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  Coverage           ?   59.71%           
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  Files              ?      325           
  Lines              ?    40286           
  Branches           ?     6100           
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  Hits               ?    24057           
  Misses             ?    14337           
  Partials           ?     1892           

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[paddle-bot[bot]]

Thanks for your contribution!