public async Task CreatePaymentAsync()
{
//Arrange
var payment = new ProcessPaymentRequest
{
Amount = 100,
Currency = "EUR",
FullName = "Dmitriy Purtseladze",
CardNumber = "5555-5555-5555-5555",
Cvv = 123,
Expiry = "08/22"
};
//Act
await _subject.ProcessPaymentAsync(payment);
//Assert
await Mediator.Received().Send(Arg.Any <ProcessPaymentCommand>());
}