Also fix a couple of broken tests in Consequences:
- For createaccount, $user->addToDatabase must be called before
testForAccountCreation, or it will throw a CannotCreateActorException.
- In testThrottleLimit, also set wgAbuseFilterEmergencyDisableThreshold
to avoid relying on the local config.
Bug: T201193
Change-Id: If1a50b0a729e4d554485f2e2225d5877510966b6
