Gocardless-pro

- Added new field called "status" to GET /billing_requests/<billing_request_id>/institutions endpoint

- Added new endpoint `/balance` that the balances for a creditor

- Added `status` filter parameter to Mandate Import Entries.
- Added `processing_errors` response field to Mandate Import Entry.

- Added `mandate_request[consent_type]` parameter to Billing Request creation.
- Added `constraints[payment_method]` parameter to Billing Request creation.
- Added `subscription_request` parameter to Billing Request creation.
- Added `instalment_schedule_request` parameter to Billing Request creation.

- Added `/exports` APIs and added `exports` as a new event type available for Embed merchants

- Added new endpoints `/branding/logos` and `/branding/payer_themes` available for Embed merchants