[FIX] website: fix scrollButton option on events

On events, or in every part of the website that was built without
sections, the scroll button of a dropped snippet was not effective.

This was because we were targeting the next section, which was not there
in the previous case. Yet, we want it to scroll to the next element,
even if it is not a section.

task-2566338

closes odoo/odoo#72733

X-original-commit: 439381aa98c3b1e03513edb45cda284f4627d2a8
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

addons/website/static/src/js/content/snippets.animation.js

@@ -965,9 +965,9 @@ registry.ScrollButton = registry.anchorSlide.extend({
      */
     _onAnimateClick: function (ev) {
         ev.preventDefault();
-        const $nextSection = this.$el.closest('section').next('section');
-        if ($nextSection.length) {
-            this._scrollTo($nextSection);
+        const $nextElement = this.$el.closest('section').next();
+        if ($nextElement.length) {
+            this._scrollTo($nextElement);
         }
     },
 });