refactor: generate notification connection request (pending, accepted) - WPB-11659

[jullianm]

WPB-11659 [iOS] Generate UNNotificationContent for new user connection request

Key points

This PR is about generating notification content related to the user connection (pending, accepted) populating the right data in the notification (title, body, sound, category..).

Testing

• Notification for user connection pending and accepted is correctly populated.

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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.

[github-actions]

Test Results

    3 files      4 suites   4m 24s ⏱️
3 339 tests 3 311 ✅ 28 💤 0 ❌
3 349 runs  3 321 ✅ 28 💤 0 ❌

Results for commit 3c90179.

[datadog-wireapp]

Datadog Report

Branch report: refactor/generate-notification-connection-request
Commit report: 18b4bff
Test service: wire-ios-mono

✅ 0 Failed, 3200 Passed, 28 Skipped, 2m 20.6s Total Time