Update dependency Microsoft.NET.Test.Sdk to 18.4.0

Author: renovate[bot]

src/dotnet/Directory.Packages.props

@@ -9,7 +9,7 @@
     <!-- Test-only -->
     <ItemGroup>
         <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.1"/>
-        <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.0.1"/>
+        <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.4.0"/>
         <PackageVersion Include="xunit" Version="2.9.3"/>
         <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.5"/>
         <PackageVersion Include="coverlet.collector" Version="6.0.4"/>