refactor(test): extract assertStatus helper to testutil

[jackby03]

This PR extracts the duplicate assertStatus helper function previously copied across 11 module test files into internal/modules/util/testutil.

🎯 What

Extracted assertStatus to testutil.AssertStatus(t, findings, id, want) and removed duplicated implementations in auditd, containers, crypto, firewall, logging, mac, network, ntp, ssh, updates, and users module test files. Added unit test coverage for testutil.AssertStatus.

💡 Why

Deduplicating test helper functions improves code health, readability, and maintainability across module unit tests.

✅ Verification

• Added unit tests in internal/modules/util/testutil/testutil_test.go verifying AssertStatus.
• Ran go test ./... and confirmed all tests compile and pass cleanly.

✨ Result

Code base duplicate helper logic eliminated and replaced with shared testutil.AssertStatus.

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PR created automatically by Jules for task 5934071554595623506 started by @jackby03

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