[FIX] base: generate field translations based on index key

The ir_translation table has an index on the (name, lang, type and value)
key, however this index was not being used when generating field
translations because the column `type` was missing!

With this commit, we fully utilize the index when generating field
translations.

With the eCommerce with categories and 4k+ products, the time to charge
products per category would be around 4-5s; With this patch it is
reduced to 1-2s.

opw-1961665

closes odoo/odoo#33504

Signed-off-by: Raphael Collet (rco) <rco@openerp.com>

odoo/models.py

@@ -3961,8 +3961,7 @@ class BaseModel(MetaModel('DummyModel', (object,), {'_register': False})):
             # The quotes surrounding `ir_translation` are important as well.
             unique_translation_subselect = """
                 (SELECT res_id, value FROM "ir_translation"
-                 WHERE name=%s AND lang=%s AND value!=''
-                 ORDER BY res_id, id DESC)
+                 WHERE type='model' AND name=%s AND lang=%s AND value!='')
             """
             alias, alias_statement = query.add_join(
                 (table_alias, unique_translation_subselect, 'id', 'res_id', field),