Feat/add electron browser to playwright

[calvinbayer]

Motivation/Description of the PR

• My application gets deployed to the web and also packaged into an Electron container. Therefore, I'd like to test it in both the web and the container. Unfortunately, that is not yet possible with CodeceptJs and I dislike having to maintain two different setups. Playwright allows to launch electron containers the same way you can launch browsers (playwright.chromium.launch(...) vs. playwright._electron.launch(...)). I'd love to see this additional "browser" being added to the CodeceptJs Playwright helper and would be willing to do that if you are in favor of the idea.
• Resolves How can I attach to electron window? #825

Applicable helpers:

• WebDriver
• Puppeteer
• Nightmare
• REST
• FileHelper
• Appium
• Protractor
• TestCafe
• Playwright

Applicable plugins:

• allure
• autoDelay
• autoLogin
• customLocator
• pauseOnFail
• puppeteerCoverage
• retryFailedStep
• screenshotOnFail
• selenoid
• stepByStepReport
• wdio

Type of change

• 🔥 Breaking changes
• 🚀 New functionality
• 🐛 Bug fix
• 📋 Documentation changes/updates
• ♨️ Hot fix
• 🔨 Markdown files fix - not related to source code
• 💅 Polish code

Checklist:

• Tests have been added
• Documentation has been added (Run npm run docs)
• Lint checking (Run npm run lint)
• Local tests are passed (Run npm test)

[DavertMik]

Hey, this PR is awesome!
But it needs to be documented so everyone knew how to test Electron apps!

Could you add a section about Electron testing to a guide here https://github.com/codeceptjs/CodeceptJS/blob/3.x/docs/playwright.md

And list electron as an option here:
https://github.com/codeceptjs/CodeceptJS/blob/3.x/lib/helper/Playwright.js#L61

Thanks!

[DavertMik]

Suggested change

	const availableBrowsers = ['chromium', 'webkit', 'firefox', '_electron'];
	const availableBrowsers = ['chromium', 'webkit', 'firefox', 'electron'];

Maybe let's just call it electron? Why not?

[calvinbayer]

Hey,
sorry I had a few busy weeks and it took me a while to finish this PR. Please have a look again, I have renamed the browser from _electron to electron and added some documentation as well as some other needed changes.

[DavertMik]

Thanks @cbayer97
This was a very hard week (month) for me so I just got here to look at updated PR. Everything looks good! 👍