fix: validate payload length - WPB-24142

[johnxnguyen]

WPB-24142 [iOS] Validate payload length

Issue

This PR contains a small improvement to drop invalid payloads

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Checklist

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

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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
1 New issue
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

   11 files  1 071 suites   11m 0s ⏱️
8 044 tests 8 015 ✅ 28 💤 1 ❌
8 056 runs  8 028 ✅ 28 💤 0 ❌

For more details on these failures, see this check.

Results for commit 15fcae4.

Summary: workflow run #23246814301
Allure report (download zip): html-report-28626-fix_validate-payload-length-wpb-24142