* fix(bench): new-site params for root db credentials

allow root credentials for postgresql
use common cli option name for both database types

* fix(bench): backward compatible db params

Co-authored-by: gavin <gavin18d@gmail.com>

* fix(bench): use common db cred params

use --db-root-username and --db-root-password

* feat(bench): add --set-default to bench new-site

* fix: do not set default root user

* fix: indentation

Co-authored-by: gavin <gavin18d@gmail.com>