[FIX] web: fix the scrollbar compensation for rtl pages

In Website, since the `#wrapwrap` element is being scrolled on the
pages, we added a function called `compensateScrollbar` (added by this
commit [1]) that adds space on the right side equal to the width of the
scrollbar when a modal is open or to adjust the position of the fixed
header when a page is scrolled.

However, this `compensateScrollbar` function did not handle RTL pages
correctly, where the scrollbar is on the left instead of the right. As a
result, on RTL language pages, this space was added on the wrong side.

This commit fixes the issue by placing the space on the left instead on
RTL pages.

Steps to reproduce the bug:
- Select Arabic as the primary language for a website.
- In edit mode, drag and drop a popup onto a page.
- Bug: When the popup is open, space is added on the right to compensate
for the scrollbar, but it should be on the left instead.

[1]: https://github.com/odoo/odoo/commit/ebd0c90a146145079061e79c2d4c37fa182a2975



task-3102275

closes odoo/odoo#126663

X-original-commit: 9e126f7f
Signed-off-by: Benoit Socias (bso) <bso@odoo.com>

addons/web/static/src/legacy/js/libs/jquery.js

@@ -159,11 +159,15 @@ $.fn.extend({
     compensateScrollbar(add = true, isScrollElement = true, cssProperty = 'padding-right') {
         for (const el of this) {
             // Compensate scrollbar
+            const scrollableEl = isScrollElement ? el : $(el).parent().closestScrollable()[0];
+            const isRTL = scrollableEl.matches(".o_rtl");
+            if (isRTL) {
+                cssProperty = cssProperty.replace("right", "left");
+            }
             el.style.removeProperty(cssProperty);
             if (!add) {
                 return;
             }
-            const scrollableEl = isScrollElement ? el : $(el).parent().closestScrollable()[0];
             const style = window.getComputedStyle(el);
             const borderLeftWidth = parseInt(style.borderLeftWidth.replace('px', ''));
             const borderRightWidth = parseInt(style.borderRightWidth.replace('px', ''));