refactor(core): remove sudo-login-form layout

This form has never been used and existed only during the introduting the first password confirmation.
- PR 1447

Signed-off-by: Grigorii K. Shartsev <me@shgk.me>

core/templates/layout.user.php

@@ -75,16 +75,6 @@ p($theme->getTitle());
 			</div>
 		</header>
 
-		<div id="sudo-login-background" class="hidden"></div>
-		<form id="sudo-login-form" class="hidden" method="POST">
-			<label>
-				<?php p($l->t('This action requires you to confirm your password')); ?><br/>
-				<input type="password" class="question" autocomplete="new-password" name="question" value=" <?php /* Hack against browsers ignoring autocomplete="off" */ ?>"
-				placeholder="<?php p($l->t('Confirm your password')); ?>" />
-			</label>
-			<input class="confirm" value="<?php p($l->t('Confirm')); ?>" type="submit">
-		</form>
-
 		<main id="content" class="app-<?php p($_['appid']) ?>">
 			<h1 class="hidden-visually" id="page-heading-level-1">
 				<?php p(!empty($_['pageTitle'])?$_['pageTitle']:$theme->getName()); ?>