[FIX] web: Select the correct record when there is an html table in a line

Steps to follow

  - Add an HTML field in the sales order line view
  - Create a sales order
  - Add a product
  - Add a table with multiple rows in the HTML widget
  - Add a new product
  -> The new product isn't selected

Cause of the issue

  The CSS selector used for finding the record to edit was taking all tr
  element into account

Solution

  Only select direct descendants of the tbody

opw-2632817

closes odoo/odoo#76808

Signed-off-by: Lucas Perais (lpe) <lpe@odoo.com>