Add a button to hide/unhide password fields in Signup

[mohsenkhosroanjam]

Description:
As a new user, I can register via the signup form.

Actual result:
There is no button to hide/unhide the password. So I can not check my password before submitting the form.

Expected result:
Add a button to hide/unhide password fields. As a result, the new user can check and verify theirs password before submit the form.

Steps to reproduce:

1. Go to https://flash-notes.com/signup

[mohsenkhosroanjam]

@0010aor I would like to implement it. Please assign it to me.