update to .net 6

Author: pollyndos

CS/AspNetCoreCustomItem/AspNetCoreCustomItemGallery.csproj

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Project Sdk="Microsoft.NET.Sdk.Web">
   <PropertyGroup>
-    <TargetFramework>net5.0</TargetFramework>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
   <ItemGroup>    
     <PackageReference Include="DevExpress.AspNetCore.Dashboard" Version="22.1.4" />