--config flag is deprecated warning

[samrose]

MIX_ENV=prod mix run -c config/config.exs --no-deps-check --no-halt warning: the --config flag is deprecated. If you need to handle multiple configurations, it is preferrable to dynamically import them in your config files (mix) lib/mix/tasks/run.ex:158: anonymous fn/1 in Mix.Tasks.Run.process_config/1 (elixir) lib/enum.ex:783: Enum."-each/2-lists^foreach/1-0-"/2 (elixir) lib/enum.ex:783: Enum.each/2 (mix) lib/mix/tasks/run.ex:122: Mix.Tasks.Run.run/5 (mix) lib/mix/tasks/run.ex:85: Mix.Tasks.Run.run/1

An application will still start despite this warning however