Bump xunit.runner.visualstudio from 3.1.5 to 4.0.0

---
updated-dependencies:
- dependency-name: xunit.runner.visualstudio
  dependency-version: 4.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

Directory.Packages.props

@@ -11,6 +11,6 @@
     <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="10.0.301" />
     <PackageVersion Include="Moq" Version="4.20.72" />
     <PackageVersion Include="xunit" Version="2.9.3" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.5" />
+    <PackageVersion Include="xunit.runner.visualstudio" Version="4.0.0" />
   </ItemGroup>
 </Project>