TOTP: Added one-time-code autofill

During review of #4849
Tested on Firefox & Chromium desktop.

Author: ssddanbrown

resources/views/mfa/parts/verify-totp.blade.php

@@ -6,6 +6,7 @@
     {{ csrf_field() }}
     <input type="text"
            name="code"
+           autocomplete="one-time-code"
            autofocus
            placeholder="{{ trans('auth.mfa_gen_totp_provide_code_here') }}"
            class="input-fill-width {{ $errors->has('code') ? 'neg' : '' }}">