[FIX] l10n_it_account_stamp: stamp lines migration

Author: primes2h

l10n_it_account_stamp/migrations/16.0.1.0.0/pre-migration.py

@@ -0,0 +1,18 @@
+#  Copyright 2025 Sergio Zanchetta
+#  License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from openupgradelib import openupgrade
+
+
+@openupgrade.migrate()
+def migrate(env, version):
+    openupgrade.logged_query(
+        env.cr,
+        """
+        UPDATE account_move_line
+        SET
+            display_type = 'cogs'
+        WHERE
+            is_stamp_line = True;
+    """,
+    )