Plaid Search institutions

Returns a JSON response containing details for institutions that match the query parameters, up to a maximum of ten institutions per query. Versioning note: API versions 2019-05-29 and earlier allow use of the `public_key` parameter instead of the `client_id` and `secret` parameters to authenticate to this endpoint. The `public_key` parameter has since been deprecated; all customers are encouraged to use `client_id` and `secret` instead.