V15: Fix previews (#17181)

* default to preview value from cookie instead of draft.

* Fix tests

---------

Co-authored-by: Zeegaan <skrivdetud@gmail.com>

tests/Umbraco.Tests.Integration/Umbraco.PublishedCache.HybridCache/DocumentHybridCacheMockTests.cs

@@ -104,7 +104,8 @@ public class DocumentHybridCacheMockTests : UmbracoIntegrationTestWithContent
             GetRequiredService<ICacheNodeFactory>(),
             GetSeedProviders(),
             Options.Create(new CacheSettings()),
-            GetRequiredService<IPublishedModelFactory>());
+            GetRequiredService<IPublishedModelFactory>(),
+            GetRequiredService<IPreviewService>());
 
         _mockedCache = new DocumentCache(_mockDocumentCacheService, GetRequiredService<IPublishedContentTypeCache>());
     }