[FIX] stock: show move line in draft

On the package level form view, stock move lines was hidden if the
package level is in draft state.
The state is set to draft when the package level contains no move lines.

This means removing the last move line should make disappear the one2many
widget. This is problematic if we want to add a new move line
after that.

Task : 2329116

X-original-commit: 12c96af6ab4efc3d4b885d4bc984e24683a18056

addons/stock/views/stock_package_level_views.xml

@@ -29,7 +29,7 @@
                             <field name="state" invisible="1"/>
                         </tree>
                     </field>
-                    <field name="move_line_ids" attrs="{'invisible': [('state', 'in', ('draft', 'confirmed', 'cancel'))]}">
+                    <field name="move_line_ids" attrs="{'invisible': [('state', 'in', ('confirmed', 'cancel'))]}">
                         <tree>
                             <field name="product_id"/>
                             <field name="lot_id" attrs="{'column_invisible': [('parent.show_lots_m2o', '=', False)]}" groups="stock.group_production_lot"/>