Embedder too verbose

[rafaelromcar-parabol]

Issue - Bug

• How serious is the bug? P3
• OS: macOS / Linux / Windows / ?
• Browser: Chrome / Safari / Lynx / ? + version
• Node version: node --version
• NPM version: npm --version
• RethinkDB version: rethinkdb --version

The Embedder logs every time a worker does not find a job on the queue with the following message

JobQueueStream: no jobs found

When using a lot of workers, the logs are very hard to follow and read.

If there are no jobs for a worker, we should not need to communicate that to the output for each worker. We already have the "jobs per second" message showing how many jobs were processed by all workers of one Embedder in the last second.

Acceptance Criteria (optional)

Embedder log show only useful information, not repeating
Triage is performed to find the root cause of the bug, timeboxed to ~1 hour.

Estimated effort: 1 hour to triage. More if root cause is already identified.