CBG-3933 allow console logs to be rotated

[torcolvin]

• create initLumberjackLogger to initialize a lumberjack logging for files
• fix a latent bug where we leaked logCollationWorker since we would never exit the go routine. In order to close this gap, I added FileLogger.closed channel, since the following events have to happen in order:
  1. exit log rotation worker goroutine
  2. wait for log rotation worker to be done
  3. close the file handle
  4. exit logCollationWorker goroutine
• fixup docs for logging config. I noticed that https://docs.couchbase.com/sync-gateway/current/configuration-schema-bootstrap.html is missing a lot of the default values, so I added them in. Use allOf to allow for composition of data structures to override the max age parameters.

Notes:

• I don't know that max_age=6 is right for the stats logger. It probably doesn't matter since we never hit it.
• I kept the console logger max_age=0 because I wanted to conform to the API. That said, as above our API isn't documented. I don't know what it worse, losing console logs or filing up disks.

Pre-review checklist

• Removed debug logging (fmt.Print, log.Print, ...)
• Logging sensitive data? Make sure it's tagged (e.g. base.UD(docID), base.MD(dbName))
• Updated relevant information in the API specifications (such as endpoint descriptions, schemas, ...) in docs/api

Integration Tests

• GSI=true,xattrs=true https://jenkins.sgwdev.com/job/SyncGateway-Integration/2648/

[github-actions]

Redocly previews

• Admin API
• Public API
• Metric API
• Diagnostic API

[bbrks]

Haven't reviewed the API doc changes yet, but have done a full pass on the code changes.

[bbrks]

I'm OK with this approach but just have a few comments around getDeletionDirAndRegexp