Add groupCheckboxes to GroupedLayerControl

[IgniparousTempest]

Is your feature request related to a problem? Please describe.
leaflet-groupedlayercontrol supports groupCheckboxes, this would be useful to have implemented in Folium.

Describe the solution you'd like
Implementation of this missing feature.

Describe alternatives you've considered
None

Additional context
None

Implementation
I am going to make a PR for this.