Launch button for interactive app doesn't appear in developer views

[ericfranz]

If the app has no cluster specified, the launch button will not appear for the app. This is because the app is "invalid". When developing, even "invalid" apps should appear with launch buttons, so you can launch and see the interface.

This is problematic because in https://osc.github.io/ood-documentation/release-1.3/app-development/tutorials-interactive-apps/add-jupyter/copy-app.html the tutorial in step 7 claims:

You should now see a details view of the Jupyter app you just created. If you click Launch Jupyter Notebook it should open a new tab with the following warning:

This app requires a cluster that does not exist.

Instead by default you will see this:

Only after setting a valid cluster in the form.yml will you see the launch button:

[ericfranz]

Fixed with #435