Fix a PHP 8.2 deprecation notice from StaticView 2, a=chris

diff --git a/src/views/StaticView.php b/src/views/StaticView.php
index e6b9dbcd8..834ca7095 100644
--- a/src/views/StaticView.php
+++ b/src/views/StaticView.php
@@ -50,6 +50,12 @@ class StaticView extends View
      * @var array
      */
     public $head_objects;
+    /**
+     * Properties of a wiki page related to how it is output in the current
+     * activity in body of the output HTML document.
+     * @var array
+     */
+    public $page_objects;
     /**
      * Draws wiki page in a more static fashion.
      *