Move from xunit to xunit.v3

Author: rnelson

test/SlowDown.Tests/SlowDown.Tests.csproj

@@ -17,9 +17,9 @@
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="9.0.1" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="MicrosoftExtensions.Logging.Xunit" Version="1.0.0" />
-    <PackageReference Include="xunit" Version="2.9.3" />
     <PackageReference Include="Xunit.DependencyInjection" Version="10.1.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="3.0.1" />
+    <PackageReference Include="xunit.v3" Version="1.0.1" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'net8.0'">