fix: oneToOne call fails to connect when answered - WPB-21338 🍒

[github-actions]

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

• fix: oneToOne call fails to connect when answered - WPB-21338 #4021

Original PR description:

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WPB-21338 [iOS] 1:1 call fails to connect when answered on iPhone; other devices continue to ring

Issue

In some cases, when the user answers the call, the call can't be established. The problem can be easily reproduced by closing (killing) the app and receiving a call on inactive account.
This fix what implemented on iOS and AVS sides.

Solution

1. On the AVS side: Delay invocation of start/answer until AVS becomes ready
2. "AVS becomes ready" means the client has submitted to AVS the call configuration received from the backend. In this PR, I added a call to retrieve the call configuration and update AVS.

Testing

Checklist

• Title contains a reference JIRA issue number like [WPB-XXX].
• Description is filled and free of optional paragraphs.
• Adds/updates automated tests.

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UI accessibility checklist

If your PR includes UI changes, please utilize this checklist:

• Make sure you use the API for UI elements that support large fonts.
• All colors are taken from WireDesign.ColorTheme or constructed using WireDesign.BaseColorPalette.
• New UI elements have Accessibility strings for VoiceOver.

[zenkins]

✅ Auto-approved cherry-pick PR 🍒.

[github-actions]

Test Results

1 283 tests   1 283 ✅  2m 3s ⏱️
  148 suites      0 💤
    1 files        0 ❌

Results for commit b6a14ee.