Update setting production URL

[h-enk]

My advice:

• ONLY set your production URL in ./config/_default/config.toml — so, do NOT set any URL in ./config/next/config.toml or ./config/production/config.toml. Then, Hugo, Netlify and others can perfectly make out the correct URL to use.
  `

This conflicts with the documentation

Make sure to set baseURL in ./config/production/config.toml to the URL of your Doks website in production.

Originally posted by @FactoryOptic in thuliteio/doks#718 (reply in thread)