Don't warn on missing apps in smart mode

[Zebradil]

When using myks with the smart mode, it emits warnings like

12:00AM WRN [some-prod > init] Application not found app=nginx dir=envs/some/group/prod

This happens due to the change detection logic of the smart mode. If an application configuration is changed close to the environments tree root, but an environment of that tree doesn't have the app in its .environment.applications list, the warning is emitted.

The proposed solution is to skip the warning when running in smart mode.
Another option is to refine the detected changes, but this could be harder (although, more correct).