Update XML docs

Author: kjac

src/Umbraco.Core/Routing/IUrlProvider.cs

@@ -41,9 +41,11 @@ public interface IUrlProvider
     IEnumerable<UrlInfo> GetOtherUrls(int id, Uri current);
 
     /// <summary>
-    ///     Gets the preview URLs of a content item.
+    ///     Gets the preview URL of a content item.
     /// </summary>
     /// <param name="content">The content item.</param>
+    /// <param name="culture">The culture to preview (null means invariant).</param>
+    /// <param name="segment">The segment to preview (null means no specific segment).</param>
     /// <returns>The preview URLs of the content item.</returns>
     Task<UrlInfo?> GetPreviewUrlAsync(IContent content, string? culture, string? segment);