[FIX] account: invoice reference

In some cases, vendor reference for payment may already exists.

For instance in Belgium, some suppliers provide recurring invoices which
contain the same communication for the payment. From the version 9.0,
the field Vendor refrence is used for payment communication and the
maching on bank statement.

So, in this case, we have to put the communication from the payment in
this field and, as explained just above, maybe the same as on another
invoice.

Therefore, this commit provides a hook to modify/disable this behavior.

Closes #20343
opw-777608