test: fix flake in conversation search tests [WPB-22420]

[markbrockhoff]

WPB-22420 [Web] General maintenance ticket for PR merges

Pull Request

Summary

One of the tests could be come flaky due to network latency when deleting the message right before the other user searches for it. This ensures the message was already deleted for the user before he searches for it.

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Security Checklist (required)

• External inputs are validated & sanitized on client and/or server where applicable.
• API responses are validated; unexpected shapes are handled safely (fallbacks or errors).
• No unsafe HTML is rendered; if unavoidable, sanitization is applied and documented where it happens.
• Injection risks (XSS/SQL/command) are prevented via safe APIs and/or escaping.

Accessibility (required)

• I have read and this PR upholds our Accessibility Best Practices.

Standards Acknowledgement (required)

• I have read and this PR upholds our Coding Standards and Tech Radar Choices.

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Screenshots or demo (if the user interface changed)

Notes for reviewers

• Trade-offs:
• Follow-ups (linked issues):
• Linked PRs (e.g. web-packages):

[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]

🔗 Download Full Report Artifact

🧪 Playwright Test Summary

• ✅ Passed: 260
• ❌ Failed: 0
• ⏭ Skipped: 16
• 🔁 Flaky: 4
• 📊 Total: 280
• ⏱ Total Runtime: 495.7s (~ 8 min 16 sec)

specs/Conversations/conversations.spec.ts (❌ 0 failed, ⚠️ 1 flaky)

• ⚠️ Conversations > I want to see a system message with all group members mentioned on creating a group (tags: TC-2965, regression)

specs/Notifications/notifications.spec.ts (❌ 0 failed, ⚠️ 1 flaky)

• ⚠️ Notifications > No notification shown when selecting 'Off' in preferences (tags: TC-1453, regression)

specs/Reactions/reactions.spec.ts (❌ 0 failed, ⚠️ 1 flaky)

• ⚠️ Reactions > Verify likes are reset if you edited message (tags: TC-1538, regression)

specs/SelfDeletingMessages/selfDeletingMessages.spec.ts (❌ 0 failed, ⚠️ 1 flaky)

• ⚠️ Self Deleting Messages > Verify sending ephemeral text message in 1:1 (tags: TC-657, regression)