Fix breaking change

Author: bergmania

src/Umbraco.Core/DependencyInjection/UmbracoBuilder.CollectionBuilders.cs

@@ -1,3 +1,4 @@
+using System;
 using Umbraco.Cms.Core.Composing;
 using Umbraco.Cms.Core.Dashboards;
 using Umbraco.Cms.Core.Media;
@@ -84,6 +85,10 @@ public static IUmbracoBuilder AddEmbedProvider<T>(this IUmbracoBuilder builder)
             return builder;
         }
 
+        [Obsolete("Use AddEmbedProvider instead. This will be removed in Umbraco 10")]
+        public static IUmbracoBuilder AddOEmbedProvider<T>(this IUmbracoBuilder builder)
+            where T : class, IEmbedProvider => AddEmbedProvider<T>(builder);
+
         /// <summary>
         /// Register a section.
         /// </summary>