refactor: generate notification user contact join - WPB-11660

[jullianm]

WPB-11660 [iOS] Generate UNNotificationContent for user contact join

Key points

This PR is about generating notification content related to the user join event (connections) populating the right data in the notification (title, body, sound, category..).

Testing

• Notification for user join 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   5m 12s ⏱️
3 339 tests 3 311 ✅ 28 💤 0 ❌
3 349 runs  3 321 ✅ 28 💤 0 ❌

Results for commit 0eb4f18.

[datadog-wireapp]

Datadog Report

Branch report: refactor/generate-notification-connections
Commit report: 834074d
Test service: wire-ios-mono

✅ 0 Failed, 3200 Passed, 28 Skipped, 3m 10.71s Total Time

[netbe]

LGTM;)

[johnxnguyen]

I didn't do a full review, since I think the question about whether this notification needs to be supported should be clarified first.

[johnxnguyen]

I'm confused by the naming, what is the relevance of "system message"?

[johnxnguyen]

I guess this was renamed from another PR, but it still confuses me slightly. I think the structure of the builders could follow the structure of events, so ConversationEventNotificationBuilder builds notifications for all conversation events. Internally, there could be separate builders for each events, i.e NewMessageNotificationBuilder or ConversationMemberJoinNotificationBuilder, et.c

[johnxnguyen]

I guess this is for the case where someone in your address book creates an account on Wire. But I don't think we get this event anymore, in which case I don't think we need to support this notification. Best to check with BE.