[OU-FIX] account_reconcile_oca: Avoid crash when coming from v15

When coming directly from v15, the field `reconcile_data`` doesn't
exist, so the migration scripts here will crash. The solution is to
check if the column exists and exit early if not.

account_reconcile_oca/migrations/16.0.1.2.0/pre-migration.py

@@ -3,6 +3,10 @@ from openupgradelib import openupgrade
 
 @openupgrade.migrate()
 def migrate(env, version):
+    if not openupgrade.column_exists(
+        env.cr, "account_bank_statement_line", "reconcile_data"
+    ):
+        return  # coming directly from v15, so reconcile_data doesn't exist
     # Due to the big change we did, we need to loose how data is stored
     openupgrade.logged_query(
         env.cr,