Login and Registration: Disable spellcheck for password fields.

This changeset adds `spellcheck="false"` attribute to various password fields.

The spellcheck global attribute defines whether the element may be checked for spelling errors. The `false` value indicates that the element should not be checked for spelling errors, which is relevant for a password field.

Furthermore, and as per MDN specs, using spellchecking can have consequences for users' security and privacy. The specification does not regulate how spellchecking is done and the content of the element may be sent to a third party for spellchecking results. Thus, it is recommended to set `spellcheck` attribute to `false` for elements that can contain sensitive information. Which is the case for password fields.

Props dziudek, audrasjb, gainesm, fosuahmed.
Fixes #56763.

Built from https://develop.svn.wordpress.org/trunk@55094


git-svn-id: http://core.svn.wordpress.org/trunk@54627 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/file.php

@@ -2390,7 +2390,7 @@ function request_filesystem_credentials( $form_post, $type = '', $error = false,
 <div class="ftp-password">
 	<label for="password">
 		<span class="field-title"><?php echo $label_pass; ?></span>
-		<input name="password" type="password" id="password" value="<?php echo $password_value; ?>"<?php disabled( defined( 'FTP_PASS' ) ); ?> />
+		<input name="password" type="password" id="password" value="<?php echo $password_value; ?>"<?php disabled( defined( 'FTP_PASS' ) ); ?> spellcheck="false" />
 		<?php
 		if ( ! defined( 'FTP_PASS' ) ) {
 			_e( 'This password will not be stored on the server.' );