public async Task GetRegionUsers_returnOk()
{
// Arrange
_regionService.Setup(x => x.GetRegionUsersAsync(It.IsAny <int>())).ReturnsAsync(new List <RegionUserDTO>());
int regionID = 1;
// Act
var result = await _regionController.GetRegionUsers(regionID);
// Assert
Assert.IsInstanceOf <OkObjectResult>(result);
Assert.IsInstanceOf <List <RegionUserDTO> >((result as ObjectResult).Value);
}