refactor: generate notification conversation deleted - WPB-11658

[jullianm]

WPB-11658 [iOS] Generate UNNotificationContent for deleted conversations

Key points

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

Testing

• Notification for deleted conversation 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 19s ⏱️
3 338 tests 3 310 ✅ 28 💤 0 ❌
3 348 runs  3 320 ✅ 28 💤 0 ❌

Results for commit 8ac66ab.

[datadog-wireapp]

Datadog Report

Branch report: refactor/generate-notification-conversation-deleted
Commit report: 9eabb77
Test service: wire-ios-mono

✅ 0 Failed, 3199 Passed, 28 Skipped, 2m 14.72s Total Time

[netbe]

LGTM;)

[johnxnguyen]

issue: one of the things that I don't like in our legacy code is how the actual values for the notification content separated from the content object because it usually means that there is some work involved in understanding exactly how a notification is configured.

I know that in some cases there is some complexity in generating content such as the body, and that it should also be reused among various notifications types, but I believe that mostly applies to new message notifications. In this case, I think it would be better to have the actual values closer to the content, something like:

content.body = "A conversation was deleted"
content.categoryIdentifier = .nonActionable
content.sound = .click

What do you think?