Update dependency Microsoft.NET.Test.Sdk to 18.3.0

Author: renovate[bot]

Directory.Packages.props

@@ -13,7 +13,7 @@ SPDX-License-Identifier: MIT
     <PackageVersion Include="JetBrains.Annotations" Version="2025.2.4" />
     <PackageVersion Include="MedallionShell" Version="1.6.2" />
     <PackageVersion Include="Meziantou.Xunit.ParallelTestFramework" Version="2.3.0" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.0.1" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
     <PackageVersion Include="Mono.Cecil" Version="0.11.6" />
     <PackageVersion Include="Newtonsoft.Json" Version="13.0.4" />
     <PackageVersion Include="QuikGraph" Version="2.5.0" />