message: docs: Add info about pod seeding to release notes
diff: ## v4.0.0
  ### New features
  -- ...
  +- The server can be started with a new parameter to automatically generate accounts and pods,
  + for more info see [here](guides/seeding-pods.md).
  ### Configuration changes
  You might need to make changes to your v3 configuration if you use a custom config.
  