[FIX] hr: fix error on double click of chat user name

PURPOSE

When opening the same form view 2 times in quick succession (e.g. clicking twice
on the name of an employee from a chat window), there is a traceback

SPECIFICATION

It should open public employee form and not raise any error

LINKS

Task-2371687
PR https://github.com/odoo/odoo/pull/61457

closes odoo/odoo#61971

X-original-commit: 587ed5df5b542c6c6b3f13d1e348dd28d0da1f2c
Signed-off-by: Sébastien Theys (seb) <seb@odoo.com>

addons/hr/static/src/js/chat.js

@@ -27,7 +27,9 @@ odoo.define('hr.employee_chat', function (require) {
         },
 
         destroy: function () {
-            this.$el.find('.o_employee_chat_btn').off('click');
+            if (this.$el) {
+                this.$el.find('.o_employee_chat_btn').off('click');
+            }
             return this._super();
         },