Expose "retry-after" throttle error in Canvas Data 2 DAP Client

[SpencerWilliams]

@Edina_Tipter and @LeventeHunyadi Since there is no Git issue tracking for this project, I will post my issue here.

Would it be possible to expose the "retry-after" value by possibly throwing an error with this value as a property? This would allow for me to wait after that time before trying to call the DAP API again.

Context: I have imported the DAP client library into my own code.

This is what the error message in the console says:

{"retry-after":9,"error":"Too Many Requests"}