Ingest sidekiq_client.log in the pubsub-sidekiq-inf-gprd index

Ingest #200 (closed) we should make these logs available in the index with other sidekiq logs.

This log will contain sidekiq-job related events that don't necessary happen within the sidekiq process but on all kinds of nodes.

It will need to be added to fluentd as a source, and we need to make sure we ingest that from all nodes.