add double click event hook to FigureWidget

There's a neat example in the docs showing how to add a click event handler to a scatter plot.

import plotly.graph_objects as go

import numpy as np
np.random.seed(1)

x = np.random.rand(100)
y = np.random.rand(100)

f = go.FigureWidget([go.Scatter(x=x, y=y, mode='markers')])

scatter = f.data[0]
colors = ['#a3a7e4'] * 100
scatter.marker.color = colors
scatter.marker.size = [10] * 100
f.layout.hovermode = 'closest'


# create our callback function
def update_point(trace, points, selector):
    c = list(scatter.marker.color)
    s = list(scatter.marker.size)
    for i in points.point_inds:
        c[i] = '#bae2be'
        s[i] = 20
        with f.batch_update():
            scatter.marker.color = c
            scatter.marker.size = s


scatter.on_click(update_point)

f

Would be cool if event handlers could be set to listen to double click events. Something like

scatter.on_double_click(update_point)

Start with the FigureWidget event-handler API and the click-events example linked in the issue. Determine how scatter.on_click(update_point) is exposed, then add the corresponding double-click hook so scatter.on_double_click(update_point) can receive the same callback inputs and behave consistently.