Align form creation with the prototype

[danielburnley]

Related trello card: https://trello.com/c/BnBhH6gI/239-i-need-to-create-a-new-form

To do:

• Update new form screen to match the prototype
  • Note: We can keep the email here for now as well as we dont have a space for that in the prototype yet
• Redirect to form overview screen on creation (Depends on Create initial form overview screen #43)
• Journey covered in automated tests
  • Note: These should include request specs and front end tests using cypress