[Browser tests] Disable svwikt production test as it's NS_USER-only

Unlike all other wikis with VisualEditor enabled, svwiktionary is set to
only allow VisualEditor in the User: namespace, so causing the production
test (which blindly tries to make a dummy edit in the main namespace) to
fail. For now, will just remove this one from the test.

Change-Id: I6f1eb8bd6bd384e1c9ca77c0036e3914f0dbe070
Merge "[Browser tests] Disable svwikt production test as it's NS_USER-only"