Keep copying readonly moves of shipments

Since cf8f1399bc1b readonly fields are not more copied but on shipment the
moves is readonly only to force the usage of Function fields.
So we could convert the readonly attribute by a static readonly states.

Closes #13004

modules/stock/shipment.py

@@ -407,8 +407,12 @@ class ShipmentIn(
                 },
             help="The moves that put the stock away into the storage area."),
         'get_inventory_moves', setter='set_inventory_moves')
-    moves = fields.One2Many('stock.move', 'shipment', 'Moves',
-        domain=[('company', '=', Eval('company'))], readonly=True)
+    moves = fields.One2Many(
+        'stock.move', 'shipment', "Moves",
+        domain=[('company', '=', Eval('company'))],
+        states={
+            'readonly': True,
+            })
     origins = fields.Function(fields.Char('Origins'), 'get_origins')
     received_by = employee_field("Received By")
     done_by = employee_field("Done By")
@@ -1245,8 +1249,12 @@ class ShipmentOut(
                 },
             help="The moves that pick the stock from the storage area."),
         'get_inventory_moves', setter='set_inventory_moves')
-    moves = fields.One2Many('stock.move', 'shipment', 'Moves',
-        domain=[('company', '=', Eval('company'))], readonly=True)
+    moves = fields.One2Many(
+        'stock.move', 'shipment', "Moves",
+        domain=[('company', '=', Eval('company'))],
+        states={
+            'readonly': True,
+            })
     origins = fields.Function(fields.Char('Origins'), 'get_origins')
     picked_by = employee_field("Picked By")
     packed_by = employee_field("Packed By")
@@ -1943,8 +1951,12 @@ class ShipmentOutReturn(
                 },
             help="The moves that put the stock away into the storage area."),
         'get_inventory_moves', setter='set_inventory_moves')
-    moves = fields.One2Many('stock.move', 'shipment', 'Moves',
-        domain=[('company', '=', Eval('company'))], readonly=True)
+    moves = fields.One2Many(
+        'stock.move', 'shipment', "Moves",
+        domain=[('company', '=', Eval('company'))],
+        states={
+            'readonly': True,
+            })
     origins = fields.Function(fields.Char('Origins'), 'get_origins')
     received_by = employee_field("Received By")
     done_by = employee_field("Done By")