Cypress Join and Login tests

[ddfridley]

Cypress has not been used since splitting the civil-server out of undebate. And, cypress has been updated to 29 due to security alerts.
Jest has also been updated.

• Get Cypress and Jest working of this repo
• Create a Cypress test for the join page that checks if a new user can create an account
• Create a Cypress test for the login page that checks if an existing user can login
• Create other cypress tests for the Join component and authform

[ice1080]

Fyi this issue is mostly completed by #33 (if not fully completed by it)