Fixed .NET compatibility of ported features. (#7782)

Author: michaelstaib

src/HotChocolate/AspNetCore/src/AspNetCore.Authorization/DefaultAuthorizationHandler.cs

@@ -43,8 +43,9 @@ public DefaultAuthorizationHandler(
             throw new ArgumentNullException(nameof(authorizationPolicyProvider));
         _authorizationPolicyCache = authorizationPolicyCache ??
             throw new ArgumentNullException(nameof(authorizationPolicyCache));
-
+#if NET7_0_OR_GREATER
         _canCachePolicies = _authorizationPolicyProvider.AllowsCachingPolicies;
+#endif
     }
 
     /// <summary>

src/HotChocolate/Core/src/Types/Types/Directives/SemanticNonNullDirective.cs

@@ -5,7 +5,11 @@ namespace HotChocolate.Types;
 [DirectiveType(WellKnownDirectives.SemanticNonNull, DirectiveLocation.FieldDefinition, IsRepeatable = false)]
 public sealed class SemanticNonNullDirective(IReadOnlyList<int> levels)
 {
+#if NETSTANDARD2_0
+    [GraphQLType(typeof(ListType<NonNullType<IntType>>))]
+#else
     [GraphQLType<ListType<NonNullType<IntType>>>]
+#endif
     [DefaultValueSyntax("[0]")]
     public IReadOnlyList<int>? Levels { get; } = levels;
 }