Fix RemovedInWagtail80 deprecation warning

> RemovedInWagtail80Warning: `construct_wagtail_userbar` hook functions should accept a `page` argument in third position - bakerydemo.base.wagtail_hooks.replace_userbar_accessibility_item needs to be updated

bakerydemo/base/wagtail_hooks.py

@@ -37,7 +37,7 @@ class CustomAccessibilityItem(AccessibilityItem):
 
 
 @hooks.register("construct_wagtail_userbar")
-def replace_userbar_accessibility_item(request, items):
+def replace_userbar_accessibility_item(request, items, page):
     items[:] = [
         CustomAccessibilityItem() if isinstance(item, AccessibilityItem) else item
         for item in items