feat: Support for overflow in comparison_plotters

[jburzy]

There is currently no option in plot_data_model_comparison/plot_model for different flow options in histplot. I believe this is more complicated than just allowing additional kwargs for histplot because the conversion to EnhancedPlottableHistogram that is done in these functions drops the overflow information (in histplot the flow information is returned via the get_plottables() function and handled separately). I think the best solution would be to update how the EnhancedPlottableHistogram conversion handles the flow information to allow get_plottables() to work correctly with EnhancedPlottableHistogram inputs

[andrzejnovak]

Thanks for the report!