when setting env, the application must be loaded (and not started) before calling Application.put_env, otherwise if the app is not loaded when env is set, the defaults from the app will overwrite the ones set by local_cluster
start only already started applications: sometimes there're apps that are loaded and not started, like the ones that have runtime: false in mix.exs. Starting them may lead to errors
This patch fixes two minor issues:
runtime: false
in mix.exs. Starting them may lead to errors