Support A Well-Known URL for Changing Passwords

[rwinch]

Expected Behavior
Spring Security should support https://wicg.github.io/change-password-url/index.html

[evgeniycheban]

@rwinch I would like to work on this.

[rwinch]

Thank you for volunteering! The issue is yours Please let me know if I can be of any help

[evgeniycheban]

@rwinch I've submitted PR.

Please take a look when you have a moment.