Replace the [GR4VY_ID] with your instance identifier and [TOKEN] with the JWT created in step 2.
Additional options can be provided when launching the SDK.
The Gr4vy ID is the unique identifier for your instance. Together with the environment
(sandbox or production) it is used to connect to the right APIs.
Once launched, the SDK will send events when a transaction was created and for some failures.
To handle these events, add a new event listener to the SDK.