CameraDisplay exception in jupyter notebook with widget backend

[maxnoe]

Describe the bug

See below

To Reproduce

Put the following in a jupyter lab notebook with matplotlib 3.10.7, ipympl 0.9.8

import numpy as np
import astropy.units as u
import matplotlib.pyplot as plt

from ctapipe.visualization import CameraDisplay



%matplotlib widget


fig, ax = plt.subplots(layout="constrained", figsize=(6, 5))

display = CameraDisplay(geometry_eng_frame)
display.add_colorbar()

This raises the following error:

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
Cell In[10], line 3
      1 fig, ax = plt.subplots(layout="constrained", figsize=(6, 5))
----> 3 display = CameraDisplay(geometry_eng_frame)
      4 display.add_colorbar()

File [/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py:185](http://127.0.0.1:8888/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py#line=184), in CameraDisplay.__init__(self, geometry, image, cmap, norm, autoscale, title, allow_pick, autoupdate, show_frame, ax)
    183     self.image = image
    184 else:
--> 185     self.image = np.zeros_like(self.geom.pix_id, dtype=np.float64)
    187 self.norm = norm
    188 self.auto_set_axes_labels()

File [/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py:380](http://127.0.0.1:8888/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py#line=379), in CameraDisplay.image(self, image)
    378 if self.autoscale:
    379     self.pixels.autoscale()
--> 380 self._update()

File [/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py:385](http://127.0.0.1:8888/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py#line=384), in CameraDisplay._update(self)
    383 """signal a redraw if autoupdate is turned on"""
    384 if self.autoupdate:
--> 385     self.update()

File [/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py:390](http://127.0.0.1:8888/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/ctapipe/visualization/mpl_camera.py#line=389), in CameraDisplay.update(self)
    388 """redraw the display now"""
    389 fig = self.axes.figure
--> 390 fig.canvas.draw()
    391 if self.colorbar is not None:
    392     from matplotlib.figure import SubFigure

File [/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/matplotlib/backends/backend_webagg_core.py:191](http://127.0.0.1:8888/fefs/aswg/workspace/maximilian.linhoff/.conda/envs/check_dl0/lib/python3.12/site-packages/matplotlib/backends/backend_webagg_core.py#line=190), in FigureCanvasWebAggCore.draw(self)
    189     super().draw()
    190 finally:
--> 191     self.manager.refresh_all()

AttributeError: 'NoneType' object has no attribute 'refresh_all'

Expected behavior
Camera Display appears with colorbar.