Switch to latest version of GenHTTP web server engine (#5341)

frameworks/CSharp/genhttp/Benchmarks/Benchmarks.csproj

@@ -16,8 +16,8 @@
   </PropertyGroup>
     
   <ItemGroup>
-    <PackageReference Include="GenHTTP.Core" Version="2.5.0" />
-    <PackageReference Include="GenHTTP.Modules.Webservices" Version="2.5.0" />
+    <PackageReference Include="GenHTTP.Core" Version="2.6.0" />
+    <PackageReference Include="GenHTTP.Modules.Webservices" Version="2.6.0" />
   </ItemGroup>
   
 </Project>