chore(deps): update dependency microsoft.net.test.sdk to 18.4.0

Author: renovate[bot]

src/Directory.Packages.props

@@ -25,7 +25,7 @@
     <PackageVersion Include="Avalonia.Diagnostics" Version="11.3.13" />
     <PackageVersion Include="Avalonia.Desktop" Version="11.3.13" />
     <PackageVersion Include="Microsoft.Extensions.Logging.Debug" Version="10.0.5" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.4.0" />
     <PackageVersion Include="System.Formats.Asn1" Version="10.0.5" />
     <PackageVersion Include="PublicApiGenerator" Version="11.5.4" />
     <PackageVersion Include="Splat" Version="19.3.1" />