Accordion's active does not work correctly

[rafgonsi]

ALL software version info

Python 3.7.6, panel==0.10.3

Description of expected behavior and the observed behavior

1. I would expect accordion.active to return list of active cards. Now it returns an empty list even if some card is open.
2. Also setting values to accordion.active I would expect to open only selected cards. Now it opens selected cards, but does not close the ones that were not selected.

Complete, minimal, self-contained example code that reproduces the issue

# based on https://panel.holoviz.org/reference/layouts/Accordion.html
import panel as pn
pn.extension()

from bokeh.plotting import figure

p1 = figure(width=300, height=80, name='Scatter', margin=5)
p1.scatter([0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 2, 1, 0])

p2 = figure(width=300, height=80, name='Line', margin=5)
p2.line([0, 1, 2, 3, 4, 5, 6], [0, 1, 2, 3, 2, 1, 0])

accordion = pn.Accordion(p1, p2)
accordion

accordion.active

accordion.active = [0]

Screenshots or screencasts of the bug in action