new: Allow to reset passwords

[marien-probesys]

Related issue(s)

#650

How to test manually

1. go to the reset password page from the login page
2. enter an email of an account not managed by LDAP (e.g. alix@example.com)
3. verify that an information tells you an email has been sent and that the user received the email
4. click on the link of the email
5. enter a new password and submit
6. verify that you're redirected to the login page and that an information tells you the password changed
7. try to login with the new password
8. verify it works

Checklist

• code is manually tested
• permissions / authorizations are verified
• data can be imported correctly
• interface works on both mobiles and big screens
• interface works in both light and dark modes
• interface works on both Firefox and Chrome
• accessibility has been tested
• tests are up-to-date
• locales are synchronized
• copyright notices are up to date
• documentation is up to date (including migration notes)