fix: make auto_docstring import-time performance test robust to timing noise.

[deepresearcher08]

What does this PR do?

-tests/utils/test_auto_docstring.py

• Switched from time.perf_counter() to time.process_time() to prevent inflation of measurement from the co-tenant scheduling noise.
• Use min() over 10 iterations instead of median() over 5, the minimum is the sample least contaminated by unrelated system activity.
• Replace the percentage-of-import-time ratio with an absolute per-module CPU budget (100 ms/module), so filesystem/bytecode-cache I/O in the denominator leaves the metric entirely and the bound is portable across hardware.
• Removed the now-unused statistics import.

For validation, I ran the test 8x locally (Python 3.11, torch CPU, pytest): per-module auto_docstring cost measured 5.3-6.7 ms against the 100 ms budget, giving ~15-20x headroom with a spread under 1.5 ms (vs the old ratio's ~15-point spread). Full test files collect cleanly (9 tests).

Fixes #48145

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[github-actions]

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CI Security Gate — automatic approval blocked

This PR was not automatically approved for CI because the security gate failed.

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• A new high-severity security issue was detected in the changed Python files (Bandit check)

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[github-actions]

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CI recap

Dashboard: View test results in Grafana
Latest run: 32479139741:2
Result: success | Jobs: 3 | Tests: 33 | Failures: 0 | Duration: 2m 19s