[FIX] base: translate error messages at failed import

Forward-port of ffee5bdbd12b0080349da515d01981943355d0cd;
because of 1a315e87 by the same author,
only the following are left:
- we need to translate the untranslated message
- give the temporary cursor a name different from cursor or cr
  so that _'s _get_cr method does not get the closed cursor

closes odoo/odoo#41140

X-original-commit: 92687303
Signed-off-by: Nans Lefebvre (len) <len@odoo.com>