[REF] website, *: replace legacy dialog with OWL Dialog

*: test_website, web_editor, website_sale

The goal of this commit is to replace all Dialog in the Website Editor
flow with OWL Dialog. This uses the new `bindService` and `call` methods
available on legacy widgets. The replacements mainly use the
ConfirmationDialog component, but some had to have custom-made dialogs.

closes odoo/odoo#138947

Signed-off-by: Francois Georis (fge) <fge@odoo.com>

addons/website/static/src/js/user_custom_javascript.js

@@ -7,14 +7,17 @@
 // world !' message in a popup:
 //
 /*
-import Dialog from '@web/legacy/js/core/dialog';
+import { ConfirmationDialog } from '@web/core/confirmation_dialog/confirmation_dialog';
 import publicWidget from '@web/legacy/js/public/public_widget';
 
 publicWidget.registry.HelloWorldPopup = publicWidget.Widget.extend({
     selector: '#wrapwrap',
 
-    start: function () {
-        Dialog.alert(this, "Hello, world!");
+    init() {
+        this.dialog = this.bindService("dialog");
+    },
+    start() {
+        this.dialog.add(ConfirmationDialog, { body: 'Hello World' });
         return this._super.apply(this, arguments);
     },
 });