More testing improvements

[bmos]

What's Changed

• Refactor session and driver creation to better handle errors and avoid re-running tests with meaningless parameterization
• Run ruff format to remove whitespace from empty line
• In tests that don't rely on session fixture, add check for discarded browser context
• List each test result individually in github actions log
• Opt-in to Selenium 5 default behavior (upgrading webdriver to match selenium version) in github actions workflow

Why?

Remaining intermittent test failures occur during session object creation
I ran tests repeatedly on my branch and didn't get any failures, so I think this actually deals with all the remaining intermittent issues.

[lordjabez]

@bmos thanks for all of your great work! Version 0.5.1 is finally published.