Issue #3467219 by smustgrave: Fix InvalidComponentException in links' text property

src/Plugin/UiPatterns/PropType/LinksPropType.php

@@ -102,11 +102,11 @@ class LinksPropType extends PropTypePluginBase implements ContainerFactoryPlugin
       if (array_key_exists("text", $item)) {
         // Examples: links.html.twig, breadcrumb.html.twig, pager.html.twig,
         // views_mini_pager.html.twig.
-        $item["title"] = $item["text"];
+        $item["title"] = (string) $item["text"];
         unset($item["text"]);
       }
       if (!array_key_exists("title", $item)) {
-        $item["title"] = $index;
+        $item["title"] = (string) $index;
       }
       if (array_key_exists("href", $item)) {
         // Examples: pager.html.twig, views_mini_pager.html.twig.