chore(deps): update dependency nsubstitute to v5.1.0

Author: renovate[bot]

Diff for: Directory.Packages.props

@@ -19,7 +19,7 @@
     <PackageVersion Include="FluentAssertions" Version="6.7.0" />
     <PackageVersion Include="GitHubActionsTestLogger" Version="2.3.3" />
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
-    <PackageVersion Include="NSubstitute" Version="5.0.0" />
+    <PackageVersion Include="NSubstitute" Version="5.1.0" />
     <PackageVersion Include="OpenFeature.Contrib.Providers.Flagd" Version="0.1.5" />
     <PackageVersion Include="SpecFlow" Version="3.9.74" />
     <PackageVersion Include="SpecFlow.Tools.MsBuild.Generation" Version="3.9.74" />