[FIX] account: set `payment_method_code` as readonly

The payment method code is not supposed to be changed
from an `account.payment`.

Besides, this field is only used for technical reasons,
as stated:
```
Technical field used to adapt the interface to the payment type selected.
```

There is therefore no reason to not set it as readonly.

Not setting it as reandonly could lead to a `write`
operation on the `account.payment.method` with the value
of the code, even if this is already that one set, and
such an operation could be prevented by the access rights.

opw-668624

0 files changed, 0 insertions, 0 deletions