Clean up extension methods (#17051)

Co-authored-by: Andy Butland <abutland73@gmail.com>

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

@@ -675,28 +675,6 @@ public static class FriendlyPublishedContentExtensions
     public static string Url(this IPublishedContent content, string? culture = null, UrlMode mode = UrlMode.Default)
         => content.Url(PublishedUrlProvider, culture, mode);
 
-    /// <summary>
-    ///     Gets the children of the content in a DataTable.
-    /// </summary>
-    /// <param name="content">The content.</param>
-    /// <param name="contentTypeAliasFilter">An optional content type alias.</param>
-    /// <param name="culture">
-    ///     The specific culture to filter for. If null is used the current culture is used. (Default is
-    ///     null)
-    /// </param>
-    /// <returns>The children of the content.</returns>
-    [Obsolete("This method is no longer used in Umbraco. The method will be removed in Umbraco 17.")]
-    public static DataTable ChildrenAsTable(this IPublishedContent content, string contentTypeAliasFilter = "", string? culture = null)
-        => content.ChildrenAsTable(
-            GetNavigationQueryService(content),
-            GetPublishedStatusFilteringService(content),
-            ContentTypeService,
-            MediaTypeService,
-            MemberTypeService,
-            PublishedUrlProvider,
-            contentTypeAliasFilter,
-            culture);
-
     /// <summary>
     ///     Gets the url for a media.
     /// </summary>

src/Umbraco.Web.Common/Security/EncryptionHelper.cs

@@ -3,6 +3,7 @@ using System.Diagnostics.CodeAnalysis;
 using System.Net;
 using System.Web;
 using Microsoft.AspNetCore.DataProtection;
+using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.Logging;
 using Umbraco.Cms.Core;
 using Umbraco.Cms.Web.Common.Constants;
@@ -65,14 +66,7 @@ public class EncryptionHelper
         string? additionalRouteValsAsQuery;
         if (additionalRouteVals != null)
         {
-            if (additionalRouteVals is Dictionary<string, object> additionalRouteValsAsDictionary)
-            {
-                additionalRouteValsAsQuery = additionalRouteValsAsDictionary.ToQueryString();
-            }
-            else
-            {
-                additionalRouteValsAsQuery = additionalRouteVals.ToDictionary<object>().ToQueryString();
-            }
+            additionalRouteValsAsQuery = new RouteValueDictionary(additionalRouteVals).ToQueryString();
         }
         else
         {