[Repo Assist] Update test dependencies: NUnit3TestAdapter 3.9→4.6, BenchmarkDotNet 0.14→0.15.8 (#274)

* Update test dependencies: NUnit3TestAdapter 3.9→4.6, BenchmarkDotNet 0.14→0.15.8

- NUnit3TestAdapter: 3.9.0 → 4.6.0 (fully backward-compatible with NUnit 3.x;
  brings improved test discovery and .NET 8 support)
- BenchmarkDotNet in benchmarks project: 0.14.0 → 0.15.8 (aligns with the
  version already used in the tests project)

All 317 tests pass.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* ci: trigger checks

---------

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

tests/FSharp.Control.AsyncSeq.Benchmarks/FSharp.Control.AsyncSeq.Benchmarks.fsproj

@@ -10,7 +10,7 @@
     <Compile Include="AsyncSeqBenchmarks.fs" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="BenchmarkDotNet" Version="0.14.0" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.15.8" />
     <ProjectReference Include="..\..\src\FSharp.Control.AsyncSeq\FSharp.Control.AsyncSeq.fsproj" />
   </ItemGroup>
 </Project>

tests/FSharp.Control.AsyncSeq.Tests/FSharp.Control.AsyncSeq.Tests.fsproj

@@ -17,7 +17,7 @@
     <ProjectReference Include="..\..\src\FSharp.Control.AsyncSeq\FSharp.Control.AsyncSeq.fsproj" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="NUnit" Version="3.9.0" />
-    <PackageReference Include="NUnit3TestAdapter" Version="3.9.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="4.6.0" />
     <PackageReference Include="System.Threading.Channels" Version="*" />
   </ItemGroup>
 </Project>