Rails logs: database_load_balancing accounts for ~10% of rails log records

The bulk of our rails logs (our highest volume log stream) consists of log entries from json.subcomponent: database_load_balancing. In particular this message:

json.message: Host is online after replica status check

Looking over a 24 hour time range (source), 197,036,856 out of 2,576,271,127 records were of subcomponent database_load_balancing. That's 7.6%, at peak times the percentage can be even higher.

At the current volume these logs are excessive. I propose we drop them and perhaps figure out a more efficient way to expose this information.

We can drop them without having to modify any application code by adding a rule to pubsubbeat.