Documentation: README disagrees with https://matplotlib.org/ipympl/

Describe the issue

The current README specifies that to use ipympl you simply use the following magic:

%matplotlib widget

However, the documentation specifies the following magic:

%matplotlib ipympl

The latter works for my system, while the former does not.

Versions

 3.10.3 (main, Mar 18 2022, 08:05:10) [GCC 9.4.0]
ipympl version: 0.8.8
Selected Jupyter core packages...
IPython          : 8.2.0
ipykernel        : 6.12.1
ipywidgets       : 7.7.0
jupyter_client   : 7.2.1
jupyter_core     : 4.9.2
jupyter_server   : 1.16.0
jupyterlab       : 3.3.2
nbclient         : 0.5.13
nbconvert        : 6.4.5
nbformat         : 5.3.0
notebook         : 6.4.10
qtconsole        : not installed
traitlets        : 5.1.1
Known nbextensions:
  config dir: /home/bthayer/.cache/pypoetry/virtualenvs/opf-7uscUANZ-py3.10/etc/jupyter/nbconfig
    notebook section
      jupyter-matplotlib/extension  enabled 
      - Validating: OK
      jupyter-js-widgets/extension  enabled 
      - Validating: OK
JupyterLab v3.3.2
/home/bthayer/.cache/pypoetry/virtualenvs/opf-7uscUANZ-py3.10/share/jupyter/labextensions
        jupyter-matplotlib v0.10.5 enabled OK
        @jupyter-widgets/jupyterlab-manager v3.1.0 enabled OK (python, jupyterlab_widgets)

将 README.md 与 https://matplotlib.org/ipympl/ 上当前的 ipympl 文档进行比较，并在报告的 Jupyter 设置中验证两个魔术命令。更新过时的示例，使 README 与文档保持一致，然后确认所示用法与受支持的命令相符。