Check for missing deployment

[lyuboxa]

Description of change

Fixes an issue introduced by #753 where a missing deployment results in

> m apps deploy
Validating your app.json...
	✔ Checked your language is "golang"
	✔ Checked your application name is "filter-app"
Checking for uncommitted changes...
	✔ No uncommitted changes!
Error: could not find deployment

A missing deployment may be the result of an interrupted deployment due to build issues, if this does happen the app should be considered modified.

Type of change

• New feature
• Bug fix
• Refactor
• Documentation

How was this tested?

• Unit Tests
• Tested in staging
• Tested in minikube

Demo

before	after

Additional references

Documentation updated