[FIX] account: sequence of statement

It can happen that the account moves generated during reconciliation
from a bank statement with several lines have the same number.

This is a complement of commit 9365482df0. The order of statement lines
is not derterministic since it is based on `statement_id desc,
sequence`. Therefore, at each call of `process_reconciliation`, the
array `self.statement_id.line_ids.ids` can be different.

opw-690853

addons/account/models/account_bank_statement.py

@@ -351,7 +351,7 @@ class AccountBankStatement(models.Model):
 class AccountBankStatementLine(models.Model):
     _name = "account.bank.statement.line"
     _description = "Bank Statement Line"
-    _order = "statement_id desc, sequence"
+    _order = "statement_id desc, sequence, id desc"
     _inherit = ['ir.needaction_mixin']
 
     name = fields.Char(string='Memo', required=True)