GPR | Handle Transak initialisation errors

[jhesgodi]

Summary

Handle the initialisation of Transak widget:

• Display a loader while Transak inits
• Invoke a failed to init handler if Transak does not emit the initialised event within a timeout

Notes:

• Should not use a view dispatch to set the loading view, as that will unmount the iframe and it needs to stay mounted for Transak to initialise.