[deps]: Update xunit to 2.9.3 (#1236)

This PR contains the following updates:

| Package | Change | Age | Confidence |
|---|---|---|---|
| [xunit](https://redirect.github.com/xunit/xunit) | `2.4.2` -> `2.9.3`
|
[![age](https://developer.mend.io/api/mc/badges/age/nuget/xunit/2.9.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/nuget/xunit/2.4.2/2.9.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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languages/csharp/Bitwarden.Sdk.Tests/Bitwarden.Sdk.Tests.csproj

@@ -11,7 +11,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
-    <PackageReference Include="xunit" Version="2.4.2" />
+    <PackageReference Include="xunit" Version="2.9.3" />
     <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>