Gracefully handle errors validating the form

[pepicrft]

Fixes: Bugsnag error
Fixes: Bugsnag error

WHY are these changes introduced?

After releasing 2.7.0 I noticed a new error in the app creation flow. After digging into it, I realized we are rescueing from from validation errors and returning a nil. Because we try to call a method on that returned nil value, the execution terminates.

WHAT is this pull request doing?

I changed the node_service to follow the same approach as the rails_service. If the output from the form is nil, we return printing the help to the user.

How to test your changes?

Try to create an app (e.g. shopify node create)

Update checklist

• I've added a CHANGELOG entry for this PR (if the change is public-facing)
• I've considered possible cross-platform impacts (Mac, Linux, Windows).
• I've left the version number as is (we'll handle incrementing this when releasing).
• I've included any post-release steps in the section above.

[gonzaloriestra]

🎩 ✔️