feat(cdp): expose cdp session

[pavelfeldman]

• driver-by: all optional arguments in the API should be = None, not = defaultValue.

[coveralls]

Pull Request Test Coverage Report for Build 192702471

• 105 of 119 (88.24%) changed or added relevant lines in 9 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 88.646%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
playwright/object_factory.py	12	13	92.31%
playwright/selectors.py	6	7	85.71%
playwright/async_api.py	19	21	90.48%
playwright/chromium_browser_context.py	23	27	85.19%
playwright/sync_api.py	15	21	71.43%

Totals
Change from base Build 192672313:	0.003%
Covered Lines:	3482
Relevant Lines:	3928

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💛 - Coveralls