chore(deps): update dependency xunit to 2.9.3 (#835)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [xunit](https://redirect.github.com/xunit/xunit) | `2.9.2` -> `2.9.3`
|
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|
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|
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|

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test/Directory.Build.props

@@ -11,7 +11,7 @@
     <ItemGroup>
         <PackageReference Include="FluentAssertions" Version="6.12.2" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
-        <PackageReference Include="xunit" Version="2.9.2" />
+        <PackageReference Include="xunit" Version="2.9.3" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
             <PrivateAssets>all</PrivateAssets>