public async Task GetAvaliableDistrictsAsync_ShouldReturnOnlyWolaAndBemowo()
{
_notificationSystem = new NotificationSystem(string.Empty);
var expectedResult = new List <District>
{
new District("Bemowo"),
new District("Wola")
};
var results = await _notificationSystem.GetAvaliableDistrictsAsync();
results.Should().NotBeNull();
results.Should().BeEquivalentTo(expectedResult);
}