In DonationInterface gatweay config yaml files, we can specify support for countries, currencies, and recurring both at the submethod and at the method level. Submethod-level config is supposed to override method-level config, but our logic only lets that work when the submethod-level config is more restrictive than method-level.

e.g. if you say cards support recurring but visa-debit does not, that will work. However, if you say rtbt does not support recurring, except sepadirectdebit does, that config will fail.