[Feature Request] Optionally pass errors raised from a callback specific error handler to the global error handler

[tlauli]

Thanks so much for your interest in Dash!

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Is your feature request related to a problem? Please describe.
Currently if I define on_error for both the Dash() class and a for a specific callback, the callback specific on_error overwrites the global on_error. It would be nice to have an option to chain these error handlers, so that exceptions raised from the callback specific on_error are passed on to the global on_error.

Example I can think of:

• callback specific on_error: handles user incorrectly filling in data
• global on_error: catches unexpected errors (ie. bugs) and notifies the developer

Describe the solution you'd like
Perhaps a bool argument to the callback() decorator that would enable passing uncaught exceptions from the local on_error to the global on_error, and the same argument to the Dash() class which would be used as a default for all callbacks?

Describe alternatives you've considered

• Wrapping callback specific on_error in a try catch block and calling the global error handler manually.
• Wrapping the body of a callback in a try catch block and calling the callback specific on_error manually.
  I think both of these approaches are unnecessary boiler plate.

Additional context
Add any other context or screenshots about the feature request here.