Update frontend for new password reset flow

[aapeliv]

In #4076, I introduce a new API call for resetting the password in a better way. The frontend should be updated to make use of this new functionality.

Background

• Initially we had email tokens instead of passwords: you could sign up without ever setting a password, and every time you logged in, it would just send you a token by email
• We have a "jail" system, where a user gets locked out unless they fix up something in their profile/account. We've used this e.g. for when we update ToS or similar where users have to accept before they can continue using it.

The current password reset works like this:

1. You click "reset password", web calls ResetPassword
2. Backend sends the right email a link to reset password
3. User clicks on link, takes you to the web app which calls CompletePasswordReset with nothing but the token
4. The backend clears the users' password
5. The user goes to log in again, this time it falls back to password-less login.
6. We email the user a login link
7. User clicks on link and logs in
8. User gets jailed
9. User has to reset password through Jail/SetPassword.
10. User finally gets in

Now with the new system we reduce it to 3 steps:

1. You click "reset password", web calls ResetPassword
2. Backend sends the right email a link to reset password
3. User clicks on link, takes you to the web app which calls CompletePasswordResetV2 with the reset token and a new password
4. Backend sets the user's password, and logs the user in

[aapeliv]

@bakeiro