[FIX] document_url: Improve the definition of mimetype=application/link only to records linked to a model to avoid errors with the developer model (with assets).

document_url/migrations/14.0.1.1.0/post-migration.py

@@ -0,0 +1,24 @@
+# Copyright 2021 Tecnativa - Víctor Martínez
+# 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 ir_attachment
+        SET mimetype = 'text/css'
+        WHERE mimetype = 'application/link' AND res_id = 0 AND name LIKE '%.%css'
+        """,
+    )
+    openupgrade.logged_query(
+        env.cr,
+        """
+        UPDATE ir_attachment
+        SET mimetype = 'application/javascript'
+        WHERE mimetype = 'application/link' AND res_id = 0 AND name LIKE '%.js'
+        """,
+    )