Implement the synchronization of third party data with the database

[RobinTTY]

Implement all the necessary logic to synchronize data retrieved from third party APIs with the local database where necessary. The endpoints of the GoCardless API has strict rate limitations, so calls to it should be kept limited. This will also benefit the performance of the GraphQL operations.

The basic mechanism for synchronization should be based on how frequently the data needs to be updated. The list of supported banking institutions for instance doesn't change as frequently and therefore only needs to be updated roughly once a week (or if the user specifically chooses to).