Change WebTop OTP field type to avoid browser password update

[federicoballarini]

If you enable OTP login request, at the moment, the field is a password one.
So, after a correct login, the browser always ask the user if he want to save the new password, since the OTP is always different.

Proposed solution

Change the field type to text, like NethSecurity and original Sonicle implementation.

Additional context

Code: https://github.com/NethServer/ns8-webtop/blob/main/webtop5-build/webtop-login/com/sonicle/webtop/core/tpl/page/otp.html#L206

See also

https://mattermost.nethesis.it/webtop/pl/o6m6osxfgpby3qs37f97rc85no