chore(deps): update dependency nunit3testadapter to v6

Author: renovate[bot]

ArchUnitNET.NUnitTests/ArchUnitNET.NUnitTests.csproj

@@ -10,7 +10,7 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
-    <PackageReference Include="NUnit3TestAdapter" Version="5.1.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="6.1.0" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\ArchUnitNET.NUnit\ArchUnitNET.NUnit.csproj" />