updated the way the error dialog view model is used to avoid accidentally navigating to it
updated the usages of the PingResult to reflect the new error handling workflow
made the Populate method in the CollectionViewModelBase return a Task to allow for better testing
made the DialogService use the Service pattern instead of being a static class
updated some failing/outdated tests
fixed some issues with async tests
fixed some issues with the usage of async void instead of async Task (which is a bad practice) where possible