[16.10] Replace Ai::SyncServiceTokenWorker with CloudConnector::SyncServiceTokenWorker (Iteration 2)

The operation of renaming the worker should be carried in multiple steps.

• 16.9: Introduce an identical worker with a new name. Keep the old named worker in 16.9 in case something is already scheduled.
• 16.10: Replace the references of the Ai::SyncServiceTokenWorker with CloudConnector::SyncServiceTokenWorker. This can't be done in the same milestone as previous step (16.9) to avoid the situation when the new application code schedules a job that will be executed on the Sidekiq with the old application code (will result in unknown const). Start scheduling a new worker.
• 16.11: Drop the old name.