Changing number of visible channels in the butterfly mode

Description of the problem

For raw.plot(butterfly=True) neither keyboard shortcut for changing number of visible channels, nor n_channels argument have an effect on number of visible channels.

Steps to reproduce

raw.plot(butterfly=True)

Link to data

No response

Expected results

Actual results

Additional information

Platform:         Windows-10-10.0.20348-SP0
Python:           3.10.9 (tags/v3.10.9:1dd9be6, Dec  6 2022, 20:01:21) [MSC v.1934 64 bit (AMD64)]
Executable:       C:\Users\Gennadiy\Documents\eeg-processing-pipeline\.venv\Scripts\python.exe
CPU:              Intel64 Family 6 Model 167 Stepping 1, GenuineIntel: 16 cores
Memory:           63.9 GB

mne:              1.3.0
numpy:            1.23.5 {OpenBLAS 0.3.20 with 16 threads}
scipy:            1.9.3
matplotlib:       3.6.2 {backend=QtAgg}

sklearn:          1.2.0
numba:            0.56.4
nibabel:          Not found
nilearn:          Not found
dipy:             Not found
openmeeg:         Not found
cupy:             12.0.0b3
pandas:           1.5.2
pyvista:          Not found
pyvistaqt:        Not found
ipyvtklink:       Not found
vtk:              Not found
qtpy:             2.3.0 {PyQt5=5.15.2}
ipympl:           Not found
pyqtgraph:        0.13.1
pooch:            v1.6.0

mne_bids:         Not found
mne_nirs:         Not found
mne_features:     Not found
mne_qt_browser:   0.4.0
mne_connectivity: Not found
mne_icalabel:     Not found

Start by reproducing the issue with raw.plot(butterfly=True) and check how the n_channels argument and keyboard shortcut affect the visible channels. Done means both controls change the number of displayed channels in butterfly mode, with a regression test covering the behavior.