fix: Unhandled rejection is thrown when disconnection iOS Device

[rosen-vladimirov]

In case iOS device is disconnected during LiveSync an unhandled rejection is thrown. The problem is in ios-device-lib, so update it to latest version - 0.4.12, where the issue is fixed.
Changelog: https://github.com/telerik/ios-device-lib/releases/tag/v0.4.12

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What is the current behavior?

1. Start livesync on iOS device: tns run ios
2. Apply some changes
3. After they are applied, disconnect the device
4. Unhandled rejection is thrown

What is the new behavior?

Disconnecting the device does not throw any error.