Done message appears after starting a non-existing application

[sgauruseu]

1. Create then start a sandbox, create an user(admin)
2. Install Superhero app
3. Stop Superhero app
4. run the command: enonic app start com.enonic.app.superhero -a user1:password123
5. run the same command with non-existent app name

BUG - Done is shown after starting a non-existent application

[pmi]

XP always returns 204 (No Content) status to app/start and app/stop requests so there is no way to tell if the app exists/was started.

Therefore message says:

Requesting start "app key"...Done.

Where done means that request has finished.