[FIX] web: keyboard navigation visual on row

This commit restores the highlight on the row when we navigate with the
keyboard.

Note we use `:focus-within` to maintain the highlight when we are in a
sub element of the row (e.g. `th`, `td`, some sub `div`, ...)

Steps to reproduce:
* Open a list view
* Use the keyboard to navigate => BUG

X-original-commit: 277fbfa
Part-of: odoo#101835

addons/web/static/src/views/list/list_renderer.scss

@@ -150,8 +150,8 @@
         }
 
         .o_keyboard_navigation {
-            tr:hover {
-                outline-color: transparent;
+            tr:focus-within {
+                background-color: lighten($o-form-lightsecondary, 10%);
             }
 
             th:focus-within, td:focus-within {