Remove usage of FromClaimsIdentity

src/Umbraco.Web.Common/Extensions/HttpContextExtensions.cs

@@ -35,7 +35,7 @@ namespace Umbraco.Extensions
         /// <returns>
         /// Returns the current back office identity if an admin is authenticated otherwise null
         /// </returns>
-        public static UmbracoBackOfficeIdentity GetCurrentIdentity(this HttpContext http)
+        public static ClaimsIdentity GetCurrentIdentity(this HttpContext http)
         {
             if (http == null) throw new ArgumentNullException(nameof(http));
             if (http.User == null) return null; //there's no user at all so no identity