util: change util.inspect depth default

The current default is not ideal in most use cases. Therefore it is
changed to showing unlimited depth in case util.inspect is called
directly. The default is kept as before for console.log and similar.

Using console.dir will now show a depth of up to five and
console.assert / console.trace will show a unlimited depth.

PR-URL: https://github.com/nodejs/node/pull/17907
Refs: https://github.com/nodejs/node/issues/12693


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>