Add Fenix sync integration tests to our smoketest suite

[rfk]

The Fenix repository contains some basic "live" integration tests for sync-related functionality, which attempt to connect a Fenix and a Desktop device to the same account and confirm that a bookmark/password/whatever can successfully sync between them:

https://github.com/mozilla-mobile/fenix/blob/master/docs/syncIntegrationTests.md

I think these would be a great addition to the smoke-test-fenix.py script, but unfortunately I have not yet been able to get them running reliably on my machine. I'm out of time to debug this further in the current testing-related epic, but wanted to file this issue to revisit another time.

┆Issue is synchronized with this Jira Task
┆Epic: Important backlog

[rfk]

The stumbling block I hit most recently here, was when the tests try to launch an emulator, somehow the emulator seems to get "stuck" and they can't run Fenix in it and eventually things time out. I haven't yet dug in to what might be going wrong there.

In a previous iteration, I tried connecting a physical device and running the tests. They seemed to successfully launch and control Fenix on the device. But The tests would fail when trying to sign in to FxA, I think because the screen on my device is too small and the "sign in" button is scrolled off the screen, or something like that.

[isabelrios]

So, I know this is not ideal, but you need a Pixel_3_API28 installed (see script). Otherwise the sim is not launched...
Tests are not working now due to the issue... mozilla-mobile/firefox-ios#6400
I will let you know once that's fixed...

[mhammond]

Moved to bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1865167

Change performed by the Move to Bugzilla add-on.