JupyterLabs support

[austinkline]

Is your feature request related to a problem? Please describe.
Related to #54
Query outputs are not rendered properly in JupyterLabs.

Describe the solution you'd like
All rendered widgets and magic commands which work in Notebooks should also work in labs. Ideally the extension would load automatically like it does in notebooks.

Additional context
Labs screenshot:

Note that there is not a tab output widget like there should be, and the table that is visible (you can see the first column) is not the fully formed Datatable which we use.

[mpgreg]

+1. Active use-cases limited by need to move back and forth between SageMaker NB instances for Neptune and SageMaker Studio.

[jacekko]

+1. Active use-cases limited by need to move back and forth between SageMaker NB instances for Neptune and SageMaker Studio.

+ 1

[stechr]

+1

[vishnukraj1111]

+1