public async Task HardDeletePurchase_Success_ReturnStatusCodeOk()
{
IHttpActionResult result = await purchaseController.HardDeleteProduct(new Guid("3bc4d343-1a0d-432f-a190-d8f76ebb1ab9"));
HttpJsonApiResult <PurchaseViewModel> contentResult = result as HttpJsonApiResult <PurchaseViewModel>;
Assert.AreEqual(HttpStatusCode.OK, contentResult.StatusCode);
}