[FIX] web_editor: not fail when clicking on a technical SVG

Since [1] when the stars were made available in the power box, an
exception is raised when clicking on a technical SVG of the "Steps"
block.
This happens because SVGs have their `nodeType === Node.ELEMENT_NODE`,
they have `className` and `classList` properties, but their `className`
is not a string: it is an `SVGAnimatedString`. Because of this, the
`includes` method is not available on `className`.

This commit prevents the non-existing `includes` from being called.

Steps to reproduce:
- Drop a "Steps" block into the page.
- Click on the column before the first step, at the same height as the
steps icons. (There is an hidden SVG there containing the definition of
the arrows head.)
=> Did raise an exception.

[1]: https://github.com/odoo/odoo/commit/8266b978e1bfa5bedfaf1c4fcceadd26400fc85c

task-2845963

X-original-commit: dbfbf264750a0760d4f2d96a1b7a13ea27472316
Part-of: odoo/odoo#96071

addons/web_editor/static/src/js/editor/odoo-editor/src/OdooEditor.js

@@ -3004,14 +3004,13 @@ export class OdooEditor extends EventTarget {
         }
 
         // handle stars
-        if (node.nodeType === Node.ELEMENT_NODE && node.className.includes('fa-star') &&
+        const isStar = el => el.nodeType === Node.ELEMENT_NODE && (
+            el.classList.contains('fa-star') || el.classList.contains('fa-star-o')
+        );
+        if (isStar(node) &&
             node.parentElement && node.parentElement.className.includes('o_stars')) {
-            const previousStars = getAdjacentPreviousSiblings(node, sib => (
-                sib.nodeType === Node.ELEMENT_NODE && sib.className.includes('fa-star')
-            ));
-            const nextStars = getAdjacentNextSiblings(node, sib => (
-                sib.nodeType === Node.ELEMENT_NODE && sib.className.includes('fa-star')
-            ));
+            const previousStars = getAdjacentPreviousSiblings(node, isStar);
+            const nextStars = getAdjacentNextSiblings(node, isStar);
             if (nextStars.length || previousStars.length) {
                 const shouldToggleOff = node.classList.contains('fa-star') &&
                     (!nextStars[0] || !nextStars[0].classList.contains('fa-star'));