#11606109 add: woo passwordless login

Related to ##87630

Proposed Changes

• Added branches for the login screen to handle Woo Passwordless
• Most of it was just excluding woo passwordless flow from the customised woo flows, as the existing wpcom passwordless flow handles our requirements quite well
• The other bulk of work was css changes for the updated design
• Allowed the “Send email link” and “Login with App” buttons to render as they were excluded from Woo login flow before. There was a comment about “Login with App” not working with oauth logins but it seemed to work fine for me – not sure if we should put this to more scrutiny

Figma: 4ixWMlzrxllx93tSFsCW6k-fi-9751_4240

Testing Instructions

Set up the woocommerce-start-dev-env

1. Log out of your WP.com and Woo.com or Use incognito mode to test log-in flow. You will need two accounts, one that was created passwordless-ly and one that was passworded
2. Go to woocommerce.test/start and go through the flow, doesn’t really matter what you enter. Click on the login link after you reach wpcom
3. Follow below specifications

Passwordless login

Given the user has a passwordless account
	and is logged out
	and is on the Woo Express site creation flow
When user enter their email address
	and clicks on "Continue with email"
Then a magic link will be sent to their email address
When user clicks on the magic link
Then 
    if 2FA is not enabled, they will be logged in automatically
	if 2FA is enabled, they will be prompted to complete 2FA
	and they will be redirected back to the Woo Express site creation flow

Password login

Given the user has a non-passwordless account
	and is logged out
	and is on the Woo Express site creation flow
When user continues with email
Then a password field will be shown
When user enters the correct password
	and completes 2FA (if enabled)
Then they will be logged in
	and they will be redirected back to the Woo Express site creation flow

Also, test around the existing flows and the non-passwordless flows (You can disable the feature flag by using document.cookie = 'flags=-woo/passwordless;max-age=1209600;path=/';.

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• https://wpcalypso.wordpress.com/devdocs/docs/testing/index.md for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the “[Status] String Freeze” label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the “[Status] Needs Privacy Updates” label if this pull request changes what data or activity we track or use (p4TIVU-aUh-p2)?