public async Task GetCaseDetails_UnprocessableEntity()
{
// Arrange
int caseId = 0;
string expectedError = $"Invalid CaseId: {caseId}";
// Act
ActionResult <CaseDetailsModel> response = await _sut.GetCaseDetails(caseId);
// Assert
await _mockCourtCasesService.DidNotReceive().RetrieveAsync(caseId);
var createdAtActionResult = Assert.IsType <UnprocessableEntityObjectResult>(response.Result);
Assert.Equal(expectedError, createdAtActionResult.Value);
}