Added extension method to get the icon from an PublishedContentType

This is particularly helpful (to me) when using the RenderMacro editor.

src/Umbraco.Community.Contentment/Web/Extensions/PublishedContentTypeExtensions.cs

@@ -0,0 +1,25 @@
+/* Copyright © 2021 Lee Kelleher.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+using Umbraco.Community.Contentment.DataEditors;
+using Umbraco.Core.Models.PublishedContent;
+using Umbraco.Core.Services;
+using UmbConstants = Umbraco.Core.Constants;
+
+namespace Umbraco.Web
+{
+    public static class PublishedContentTypeExtensions
+    {
+        public static string GetIcon(this IPublishedContentType contentType, IContentTypeService contentTypeService = null)
+        {
+            if (contentType != null && ContentTypeCacheHelper.TryGetIcon(contentType.Alias, out var icon, contentTypeService) == true)
+            {
+                return icon;
+            }
+
+            return UmbConstants.Icons.DefaultIcon;
+        }
+    }
+}