Bump Xunit from 2.9.2 to 2.9.3 in /src (#320)

Author: dependabot[bot]

src/Tests/Tests.csproj

@@ -6,7 +6,7 @@
   <ItemGroup>
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" PrivateAssets="all" />
     <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="XunitContext" Version="3.3.2" />
     <PackageReference Include="MarkdownSnippets.MsBuild" Version="27.0.2" />
     <PackageReference Include="Verify.Xunit" Version="28.8.1" />