Implement extend marketing website to allow password and sign up new users

[christad92]

Extend the current user journey for the requesting an account to allow the user to set up their password and creating an account right away.

For the sign up, the endpoint requires user email, password and first name and last name which is provided in the form. When the sign up is successful, we will send a request with all the user information to the OpenFn internal workflow.

• Change the primary call to action button on the landing page to: Create an account and add a new screen for setting password.
• Use the REST API from OpenFn/thunderbolt#125 to create a user
• Trigger OpenFn workflow
• Redirect the user to app.openfn.org
• https://github.com/OpenFn/marketing/issues/128
• Add recaptcha to registration page #2023

Design:
https://www.figma.com/file/I3tesaoau7ztGrKEJdPHkS/Website-(new)?type=design&node-id=3570-332&mode=design&t=ttdQOCw3l8Tm2H4P-0

[christad92]

Blocked by OpenFn/thunderbolt#125 (which is currently in review see #2043).