public void Then_Data_Is_Retrieved_Using_Paye_Only()
            {
                MockMediatr
                .Received()
                .Send(
                    Arg.Is <GetOrganisationsByPayeRef>(
                        arg => arg.PAYEReference.Equals(
                            PayeRef,
                            StringComparison.Ordinal)));

                _organisations
                .Should()
                .NotBeNull();

                _organisations
                .Value
                .Should()
                .BeEquivalentTo(ExpectedOrganisations);
            }
            public void Then_Data_Is_Retrieved_Using_Both_Paye_And_AORN()
            {
                MockMediatr
                .Received()
                .Send(
                    Arg.Is <GetOrganisationsByPayeRefAndAorn>(
                        arg => arg.PAYEReference.Equals(
                            PayeRef,
                            StringComparison.Ordinal) &&
                        arg.AccountOfficeReferenceNumber.Equals(
                            Aorn,
                            StringComparison.Ordinal)));

                _organisations
                .Should()
                .NotBeNull();

                _organisations
                .Value
                .Should()
                .BeEquivalentTo(ExpectedOrganisations);
            }