fix: flaky CommitPendingProposalsGeneratorTests - WPB-23898

[netbe]

WPB-23898 [iOS] [CI] Flaky tests on CommitPendingProposalsGeneratorTests

Issue

Sometimes CommitPendingProposalsGeneratorTests are flaky or even hangs forever on CI.

• rewrite test so it does not rely on time
• add time limit so if test fails it does not hang

Testing

• run multiple times

---

Checklist

• Title contains a reference JIRA issue number like [WPB-XXX].
• Description is filled and free of optional paragraphs.
• Adds/updates automated tests.

---

UI accessibility checklist

If your PR includes UI changes, please utilize this checklist:

• Make sure you use the API for UI elements that support large fonts.
• All colors are taken from WireDesign.ColorTheme or constructed using WireDesign.BaseColorPalette.
• New UI elements have Accessibility strings for VoiceOver.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Test Results

  1 files  132 suites   16s ⏱️
495 tests 495 ✅ 0 💤 0 ❌
496 runs  496 ✅ 0 💤 0 ❌

Results for commit 4442a31.

Summary: workflow run #22754687002
Allure report (download zip): html-report-28330-fix_hang-tests

[jullianm]

👍