Compatible with pytest-playwright 0.6.2

Because we pin playwright, we use an old pytest-playwright:
```
...
Collecting pytest-playwright (from pytest-ipywidgets==1.42.0->pytest-ipywidgets==1.42.0)
  Downloading pytest_playwright-0.5.2-py3-none-any.whl.metadata (1.5 kB)
...
```
However, the latest version (0.6.2) is not compatible with out pytest-ipywidgets library.