[FIX]intrastat declaration - weight is optional for hs codes with supplementary unit

intrastat_product/models/intrastat_product_declaration.py

@@ -413,6 +413,7 @@ class IntrastatProductDeclaration(models.Model):
                     line_qty, pce_uom
                 )
         else:
+            if not (intrastat_unit_id and suppl_unit_qty):
                 line_notes = [
                     _(
                         "Conversion from unit of measure '%s' to 'Kg' "