Add UI for blocked state

[rablador]

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This change is 

[linear]

IOS-322 Add UI for blocked state

With the upcoming changes to the packet tunnel, we should update the UI to support this new connection state. Consider whether all error types require a shortcut for sending a problem report, and have a discussion in Slack. Do try and see how this works on Desktop/Android if you lack inspiration. Until IOS-223 is merged, work off of Andrei's branch instead of main.

https://app.zeplin.io/project/5f928a32fdc9962af9018d70/screen/63c021ed2a0f36bd629f91f1

Link to all current in-app banner messages in the app on all platforms:
https://mullvad.atlassian.net/wiki/spaces/UXUI/pages/1571749912/Guide+to+writing+app+alerts

[rablador]

Reviewable status: 0 of 4 files reviewed, 1 unresolved discussion

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ios/MullvadVPN/Notifications/Notification Providers/TunnelStatusNotificationProvider.swift line 229 at r1 (raw file):

        switch error {
        case .outdatedSchema:
            errorString = "Unable to start tunnel connection after update. Please send a problem report."

Although texts have been discussed with Matilda, slightly unsure about this one.

[buggmagnet]

Nice job !

Reviewed 2 of 4 files at r1, 1 of 1 files at r2, all commit messages.
Reviewable status: 3 of 4 files reviewed, 2 unresolved discussions (waiting on @rablador)

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ios/MullvadVPN/Notifications/Notification Providers/TunnelStatusNotificationProvider.swift line 229 at r1 (raw file):

Previously, rablador (Jon Petersson) wrote…

Although texts have been discussed with Matilda, slightly unsure about this one.

Eh looks good enough IMHO. It's a pretty rare situation, so it's good to encourage problem reports in this case.

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ios/MullvadVPN/TunnelManager/TunnelManager.swift line 1103 at r2 (raw file):

            handleBlockedState(reason: .deviceRevoked)
        } else if restError.compareErrorCode(.invalidAccount) {
            handleBlockedState(reason: .invalidAccount)

I wonder how to test that .invalidAccount case... 🤔