[FIX] mrp: forgotten create decorator

Followup of
https://github.com/odoo/odoo/commit/58df6c86e06304b2c5f020e0fb93988e9e388fe0.

By default, the create, when not specified as `api.model`, supports
creation in batch (thus the batching opportunity isn't lost here).

BUT, if a create override isn't specified as `api.model` or
`api.model_create_multi`, it won't be accessible in rpc calls (because
the ORM thinks a record in self is needed).

It doesn't look like somebody can create stock move lines from the web
client itself, but it doesn't cost anything to follow the global api
(and it's clearer to clearly specify the create as create_multi).

closes odoo/odoo#48964

X-original-commit: a4fd8f8062046bcea97d9f7cfe300e19020cdecd
Signed-off-by: Victor Feyens (vfe) <vfe@odoo.com>

addons/mrp/models/stock_move.py

@@ -14,6 +14,7 @@ class StockMoveLine(models.Model):
     lot_produced_ids = fields.Many2many('stock.production.lot', string='Finished Lot/Serial Number', check_company=True)
     done_move = fields.Boolean('Move Done', related='move_id.is_done', readonly=False, store=True)  # TDE FIXME: naming
 
+    @api.model_create_multi
     def create(self, values):
         res = super(StockMoveLine, self).create(values)
         for line in res: