Deleted two local Flow jobs, created two Flow jobs that run on Sauce Labs

Deleted jobs:

browsertests-Flow-en.wikipedia.beta.wmflabs.org-linux-firefox
browsertests-Flow-test2.wikipedia.org-linux-firefox

Created jobs:

browsertests-Flow-en.wikipedia.beta.wmflabs.org-linux-chrome-sauce
browsertests-Flow-en.wikipedia.beta.wmflabs.org-linux-firefox-sauce

Paired with: Chris McMahon

Change-Id: I7b49eb8e2405136ab32ed0f8e2ac6cecdc33a4c1
Deleted local MobileFrontend jobs, refactored MobileFrontend Sauce Labs jobs

Deleted jobs:

browsertests-MobileFrontend-en.m.wikipedia.beta.wmflabs.org-linux-firefo
x
browsertests-MobileFrontend-en.m.wikipedia.org-linux-firefox
browsertests-MobileFrontend-test2.m.wikipedia.org-linux-firefox

Paired with: Chris McMahon

Change-Id: I9b76c6b09eb038e5f138e5124ac8d0d0d3033a36
Refactored Flow, MobileFrontend and VisualEditor Sauce Labs jobs. Deleted local VisualEditor jobs.

Deleted jobs:
browsertests-VisualEditor-en.wikipedia.beta.wmflabs.org-linux-firefox
browsertests-VisualEditor-production-linux-firefox
browsertests-VisualEditor-test2.wikipedia.org-linux-firefox

Paired with: Chris McMahon

Change-Id: I63e8fde9f14eb22fdf08b25749d3378445bac896