Tests: Adds end-to-end tests skeleton and basic smoke test scenario (#16901)

* Chore: Adds neccessary packages

* Wip: Initial dummy test in place

* Feature: Downloads Chromium if needed

* Fix: Adds global config object

* Refactor: Adds basic e2eScenario

* Build: Adds end to end tests to config

* Build: Changes end to end job

* Build: Adds browsers to image

* Build: Adds failing test

* Refactor: Adds first e2e-test scenario

* Fix: Ignores test output in gitignore

* Refactor: Adds compare screenshots ability

* Refactor: Removes unnecessary code

* Build: Removes jest-puppeteer

* Fix: Replaces test snapshots

* Refactor: Creates output dir if missing

* Refactor: Changes aria-labels to be more consistent

* Docs: Adds section about end to end tests

* Fix: Fixes snapshots

* Docs: Adds information about ENV variables

.gitignore

@@ -84,3 +84,5 @@ debug.test
 /packages/**/dist
 /packages/**/compiled
 /packages/**/.rpt2_cache
+
+theOutput/