[FIX] web: attach the trad alert to the form

The translation alert dialog was attached to the entire view in case no
status bar was found. This resulted in the following layout on large
screens:

    chrome
    --------------------------------------
    | alert dialog | form view | chatter |
    |              |           |         |
    --------------------------------------

Whereas when a status bar was set on the form view, the rendering was as
follow:

    chrome
    --------------------------------------
    |        status bar        | chatter |
    |       alert dialog       |         |
    |        form view         |         |
    --------------------------------------

The fix make sure the alert dialog is always placed just above the form
view just like when there is a status bar.

closes odoo/odoo#44878

Task: 2075172
X-original-commit: dacdc30681510e9c2db23610c5be5285a72a8949
Signed-off-by: Julien Castiaux <Julien00859@users.noreply.github.com>