(Bug 44225) Watchlist does not show when a watched article is added or removed from wikidata

Selenium tests for watchlist

Patchset 2: changed selector for first comment

Change-Id: Ice213ba7969105730a5d1aa639d675be2a7c9ec2
Merge "(Bug 44225) Watchlist does not show when a watched article is added or removed from wikidata"