[FIX] web_editor: more robust getRangePosition

Ensure getRangePosition do not crash if
the current selection is collapsed.

task-2154624

Part-of: odoo/odoo#71878

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

@@ -2109,7 +2109,7 @@ export function rgbToHex(rgb = '') {
 
 export function getRangePosition(el, document, options = {}) {
     const selection = document.getSelection();
-    if (!selection.isCollapsed || !selection.rangeCount) return;
+    if (!selection.rangeCount) return;
     const range = selection.getRangeAt(0);
 
     const marginRight = options.marginRight || 20;