Update dependency xunit.runner.visualstudio to v3

Author: renovate[bot]

Directory.Packages.props

@@ -15,7 +15,7 @@
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
     <PackageVersion Include="Moq" Version="4.20.70" />
     <PackageVersion Include="xunit" Version="2.8.1" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="2.8.1"/>
+    <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.0"/>
     <PackageVersion Include="coverlet.collector" Version="6.0.2"/>
   </ItemGroup>
 </Project>