fix: e2ei certificate update flow - WPB-24855 🍒

[github-actions]

This PR was automatically cherry-picked based on the following PR:

• fix: e2ei certificate update flow - WPB-24855 #4745

Original PR description:

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WPB-24855 [iOS] [Security] Certificate renewal delay occurs when renewing expired E2EI certificate by user

Issue

• The e2ei certificate enrollment flow has no activity indicators between the different steps. Under bad network conditions, it appears as if nothing is happening for a while.
• The "Update Certificate" popup can be displayed more than once.

Solution

• Add an activity indicator between each e2ei certificate enrollment flow step
• Prevent the popup from being shown during the certificate update flow

Changes

• Introduced LifecycleAwareUserAgent to wrap the different agents conforming to OIDExternalUserAgent and provide callbacks on the agent's presentation and dismissal
• Introduced E2EIEnrollmentFlow to manage the presentation of activity indicators
• Updated all the certificate enrollment flows to rely on E2EIEnrollmentFlow for a consistent UX
• Added a flag in the certificate update flow to prevent showing the "Update Certificate" popup when the flow is ongoing
• Added a debug action to trigger the "Update Certificate" popup
• Added tests

Testing

• Log in with a user in a team with e2ei enabled
• Use the developer tools to enroll an e2ei certificate with short expiration time
• Background & foreground the app, the "Update Certificate" popup should appear
• Verify that the popup doesn't appear more than once when reopening the app
• Update the certificate and verify that the activity indicators appear before & after the web view

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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.

[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