🏗 Follow up changes to integration tests on sauce labs

[rsimha]

Highlights:

• Separate duplicate integration/saucelabs test status into integration/saucelabs-stable and integration/saucelabs-beta
• Split up execution into stable and beta for push builds too
• Report results / totals / errors for beta runs
• Set an "error" status when zero tests are detected, but don't exit (allows recovery in cases like this)
• Fix logging

Fixes this error:

Follow up to #24613

[rsimha]

I was going to merge in a hurry to unblock master, until I realized that the test statuses are non-blocking. Will wait for a proper review tomorrow.

[estherkim]

Thanks for following up on my PR. I think it's cool to bubble up the test status of beta browsers, esp since these checks are non blocking.

[rsimha]

Thanks for the review! Feedback addressed.

[rsimha]

Latest comment addressed. If you think there's a better way to do this, I'm happy to abandon this PR in favor of the one you started. (I mistakenly thought this was blocking master yesterday and tried putting together a quick fix.)

[estherkim]

LGTM, thank you!

[danielrozenberg]

Eventually we wanted to make these test statuses blocking, so we'll have to make an exception in the test-status app to mark failing -beta runs as neutral instead of failed...

[rsimha]

Eventually we wanted to make these test statuses blocking, so we'll have to make an exception in the test-status app to mark failing -beta runs as neutral instead of failed...

Good point. Github allows us to make a subset of the test status checks blocking. So we can make all but the -beta check blocking if we wanted, and leave it in the failed state for visibility. Whichever way we go, there is flexibility.