Update dependency NUnit to 4.6.1

Author: dependencyupdates[bot]

src/ServiceInsight.Tests/ServiceInsight.Tests.csproj

@@ -22,7 +22,7 @@
     <PackageReference Include="GitHubActionsTestLogger" Version="3.0.4" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.5.1" />
     <PackageReference Include="NSubstitute" Version="5.3.0" />
-    <PackageReference Include="NUnit" Version="4.5.1" />
+    <PackageReference Include="NUnit" Version="4.6.1" />
     <PackageReference Include="NUnit.Analyzers" Version="4.13.0" />
     <PackageReference Include="NUnit3TestAdapter" Version="6.2.0" />
     <PackageReference Include="Shouldly" Version="4.3.0" />