dont use Assert.Fail just to cause code to throw as it fails the test in later versions of nunit

Author: Kyle McCarthy

PowerAssertTests/Approvals/EndToEndTest.cs

@@ -484,7 +484,7 @@ public void PolyAssert()
                     poly.IsTrue(() => x == 5);
                     poly.IsTrue(() => x == 6);
                     poly.IsTrue(() => x == 7);
-                    poly.Try(() => Assert.Fail("Wah wah"));
+                    poly.Try(() => throw new Exception("Wah wah"));
                     poly.Log("PolyAssert.Log messages are only printed if the test fails");
                 }
             }
@@ -506,7 +506,7 @@ public void PolyAssertCanFinishEarly()
                     poly.Log("Sometimes you do want to end the test early after all");
                     poly.StopIfErrorsHaveOccurred(); //no stop here
                     poly.Log("So just call StopIfErrorsHaveOccurred (behaves the same as disposing the PolyAssert)");
-                    poly.Try(() => Assert.Fail("Wah wah"));
+                    poly.Try(() => throw new Exception("Wah wah"));
                     poly.StopIfErrorsHaveOccurred(); //no stop here
                     poly.Log("This message should not be printed, as StopIfErrorsHaveOccurred will throw an exception this time");
                 }

PowerAssertTests/PowerAssertTests.csproj

@@ -9,9 +9,6 @@
   </PropertyGroup>
 
   <ItemGroup>
-	  <Reference Include="nunit.framework">
-		  <HintPath>..\lib\nunit.framework.dll</HintPath>
-	  </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core">
       <RequiredTargetFramework>3.5</RequiredTargetFramework>
@@ -32,6 +29,7 @@
 	  <PackageReference Include="ApprovalTests" Version="3.0.7" />
       <PackageReference Include="ApprovalUtilities" Version="3.0.7" />
 	  <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+	  <PackageReference Include="nunit" Version="3.13.1" />
 	  <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
   </ItemGroup>
 </Project>