FIX: Don't autocomplete the password confirmation field

We currently use that field for our honeypot. However, since it's a
`type=password` certain browsers like chrome were autofilling it.
Normally this isn't a problem, but if you are using subfolders on the
same host the challenge would be different and Discourse would fail the
challenge.

app/assets/javascripts/discourse/templates/modal/create-account.hbs

@@ -79,7 +79,7 @@
           <tr class="password-confirmation">
             <td><label for='new-account-password-confirmation'>{{i18n 'user.password_confirmation.title'}}</label></td>
             <td>
-              {{input type="password" value=accountPasswordConfirm id="new-account-confirmation"}}
+              {{input type="password" value=accountPasswordConfirm id="new-account-confirmation" autocomplete="false"}}
               {{input value=accountChallenge id="new-account-challenge"}}
             </td>
           </tr>