Description

This pull request addresses an issue with a test where two instances were created shortly after another leading to a Future already completed StateError.
This was caused due to side-effects of the tests where all tests passed when they were executed at once and the doubleInstance test failed when executed alone.

Also in this Pull Request is a fix for the doubleInstance error. Realized with a try/catch for only this exact error. I've used this fix because to me it feels much more elegant compared to a fix where I would basically would have to check for the same shortly after.

Alternative solution:

if (!instanceCompleter.isCompleted) {
  final _remoteConfigInstance = await _getRemoteConfigInstance();
  if (!instanceCompleter.isCompleted) {
    instanceCompleter.complete(_remoteConfigInstance);
  }
}

Related Issues

#195
flutter/flutter#38060
#28

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Breaking Change

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