[Feature] Add webdriver-like method add_experimental_option for Chromium

[BreathBlush]

Let us know what functionality you'd like to see in Playwright and what your use case is.

In selenium-python, one can set experimental option for chrome browser by Options().add_experimental_option(), among the detach: True is the most used to keep browser open after script execution done.

I've read the documentation and found nothing helpful about keeping browser open after script done. However it could be easily done in selenium-python by adding {"detach": True} in experimental option.

Would it be possible that playwright-python adding this functionality?

Do you think others might benefit from this as well?

Yes, there must be such scenarios for us to keep a detached browser.