[FW][DEL] account_payment_pro: Deleted deprecated code in account_payment_pro

[fw-bot-adhoc]

Forward-Port-Of: ingadhoc/account-payment#546

[roboadhoc]

Pull request status dashboard.

[fw-bot-adhoc]

@rov-adhoc @feg-adhoc this PR targets 18.0 and is the last of the forward-port chain.

To merge the full chain, use

@fw-bot-adhoc r+

More info at https://github.com/odoo/odoo/wiki/Mergebot#forward-port

[rov-adhoc]

@fw-bot-adhoc r+