CLI: "app get" app.yaml fallback only searches name, not scoped by owner

[theduke]

When invoking wasmer app get without a specifier, it tries to read a local app.yaml file.

If the file does not specify an app_id, it should try to search by name.
It does do so, but it appears that it currently does not scope by the owner specified in the app.yaml, but instead searches the currently active user.

This was probably not updated after adding the owner field.

Eg:

❯ wasmer app get
error: Could not find app with name 'wordpress-starter-instaboot'

vs

❯ wasmer app get wasmer-tests/wordpress-starter-instaboot
id: da_RxJIdtAUWYxK

kind: wasmer.io/App.v0
name: wordpress-starter-instaboot
owner: wasmer-tests
...

@xdoardo @ayys