[FIX] account_statement_import: abs lines don't need partner_bank_id field

Let them use the one from account moves.

account_statement_import/migrations/14.0.2.0.0/pre-migration.py

@@ -0,0 +1,26 @@
+# Copyright 2022 ForgeFlow S.L.  <https://www.forgeflow.com>
+# License LGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+from openupgradelib import openupgrade
+
+
+@openupgrade.migrate()
+def migrate(env, version):
+    if openupgrade.column_exists(
+        env.cr, "account_bank_statement_line", "partner_bank_id"
+    ):
+        # during v14, a partner_bank_id field was added to statement lines,
+        # but later we realized it is not needed.
+        # As we remove the explicit partner_bank_id in statement line, we need to transfer the
+        # values to the move for getting them through delegated inheritance
+        openupgrade.logged_query(
+            env.cr,
+            """
+            UPDATE account_move am
+            SET partner_bank_id = absl.partner_bank_id
+            FROM account_bank_statement_line absl
+            WHERE am.statement_line_id = absl.id
+                AND am.partner_bank_id IS NULL AND absl.partner_bank_id IS NOT NULL""",
+        )
+        openupgrade.lift_constraints(
+            env.cr, "account_bank_statement_line", "partner_bank_id"
+        )