Bump xunit.runner.visualstudio from 3.1.5 to 4.0.0 (#224)

Updated
[xunit.runner.visualstudio](https://github.com/xunit/visualstudio.xunit)
from 3.1.5 to 4.0.0.

<details>
<summary>Release notes</summary>

_Sourced from [xunit.runner.visualstudio's
releases](https://github.com/xunit/visualstudio.xunit/releases)._

## 4.0.0

Release notes: https://xunit.net/releases/visualstudio/4.0.0

## 4.0.0-pre.5

Release notes: https://xunit.net/releases/visualstudio/4.0.0-pre.5

## 4.0.0-pre.4

Release notes: https://xunit.net/releases/visualstudio/4.0.0-pre.4

## 4.0.0-pre.3

Release notes: https://xunit.net/releases/visualstudio/4.0.0-pre.3

Commits viewable in [compare
view](xunit/visualstudio.xunit@3.1.5...4.0.0).
</details>

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.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>