browsertests: replace -p ciwmf with --tags @clean

The ciwmf cucumber profile has been removed from the repositories,
instead QA would like to whitelist scenario using the @clean tag for
features that works on a freshly installed wiki.

Update jobs:

mwext-browsertests-MobileFrontend-phantomjs
mwext-browsertests-Translatewiki-phantomjs
mwext-browsertests-UniversalLanguageSelector-phantomjs
mwext-browsertests-VisualEditor-phantomjs

Change-Id: Ib4e874bdbefdd9730c582020a42548a5036d5a73