chore(*): Update dependency NSubstitute to v5

Author: renovate[bot]

backend/test/AcmStatisticsBackend.Tests/AcmStatisticsBackend.Tests.csproj

@@ -21,7 +21,7 @@
     <PackageReference Include="FluentAssertions" Version="6.12.0" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="7.0.20" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="NSubstitute" Version="4.3.0" />
+    <PackageReference Include="NSubstitute" Version="5.1.0" />
     <PackageReference Include="xunit" Version="2.4.2" />
     <PackageReference Include="xunit.extensibility.execution" Version="2.4.2" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">