* adds unability to see screenshare button on mobile devices test specs
* simplify code in testMobileDevice()
* userlist and chat panels should not appear at page load in mobile devices
* lint
* updates outdated audio specs due to leaveAudio changes
* correct clicks on disconnectAudio elements
* whiteboard not visible on userlistPanel or on chatPanel
* reworks mobile devices/usersagents
* fixes screenshare mobile/tablet specs
* adds whiteboardNotAppearOnMobile spec
* adds Chat Panel specification to Mobile-Tablet specs
* simplify getArgs() functions for all devices
* updating old tests + collecting more snapshots [WIP]
* updates old test suites and collects more visual regressions screenshots
* remove snapshots and their collection temporary
* run tests from packages.json
* update test execution command/export constants from .env to core/constants.js
* update tests/puppeteer/README.md file
* update LOOP_INTERVAL variable call and assign timeouts to the webcam share spec
* redefine waitForSelector func in page.js, update chat test suite specs and add poll chat message test spec
* Merge remote-tracking branch 'upstream/develop' into updating-old-tests-visual-with-visual-regressions
* update webcam test specs collecting videoPreviewTimeout and use it to wait for videoPreview selector
* update custom parameters test suite
* update breakout test suite
* update webcam layout test suite
* update multiusers test suite
* update notifications test suite
* update presentation test suite
* whiteboard test suite
* screenshare test suite
* update sharednotes test suite
* user ELEMENT_WAIT_TIME variable from timeouts constants.js
* list TEST CONSTANTS by category
* add poll test suite and assigns the right unassigned timeouts
* set test pages to headless
