public async Task UpdateOrganisationTrustees_OnSuccessfulUpdate_ReturnsOkResponse()
{
var request = AutoFixture.Create <UpdateOrganisationTrusteesRequest>();
_mediator.Setup(x => x.Send(It.IsAny <UpdateOrganisationTrusteesRequest>(), It.IsAny <CancellationToken>()))
.ReturnsAsync(true);
var result = await _controller.UpdateOrganisationTrustees(request);
result.Should().BeOfType <ActionResult <bool> >();
_mediator.Verify(x => x.Send(It.Is <UpdateOrganisationTrusteesRequest>(r => r.Trustees == request.Trustees && r.Ukprn == request.Ukprn && r.UpdatedBy == request.UpdatedBy), It.IsAny <CancellationToken>()), Times.Once);
result.Result.Should().BeOfType <OkObjectResult>();
}