[FIX] web_editor: fix overlay that is not reappearing

In some situation, the overlay does not reappear after disappearing.

Steps to reproduce:
1. add a title
2. add a few elements between title and footer so you can scroll title out of view
3. click title
4. scroll it out of view
5. click footer
6. scroll back up
7. click title
-> overlay is not reappearing[FIX]

Now overlay should not do that anymore.

closes odoo/odoo#62547

Signed-off-by: David Monjoie (dmo) <dmo@odoo.com>

addons/web_editor/static/src/js/editor/snippets.editor.js

@@ -444,6 +444,7 @@ var SnippetEditor = Widget.extend({
         // Show/hide overlay in preview mode or not
         this.$el.toggleClass('oe_active', show);
         this.cover();
+        this.toggleOverlayVisibility(show);
     },
     /**
      * Displays/Hides the editor (+ parent) options and call onFocus/onBlur if