WPCOM API: update option names in request format (#17910)

I had forgotten to do it in #16568. We must update this as well so the new options are considered valid for update.

json-endpoints/class.wpcom-json-api-site-settings-endpoint.php

@@ -76,10 +76,10 @@
 			'social_notifications_reblog'             => '(bool) Email me when someone reblogs my post?',
 			'social_notifications_subscribe'          => '(bool) Email me when someone follows my blog?',
 			'comment_moderation'                      => '(bool) Moderate comments for manual approval?',
-			'comment_whitelist'                       => '(bool) Moderate comments unless author has a previously-approved comment?',
+			'comment_previously_approved'             => '(bool) Moderate comments unless author has a previously-approved comment?',
 			'comment_max_links'                       => '(int) Moderate comments that contain X or more links',
 			'moderation_keys'                         => '(string) Words or phrases that trigger comment moderation, one per line',
-			'blacklist_keys'                          => '(string) Words or phrases that mark comment spam, one per line',
+			'disallowed_keys'                         => '(string) Words or phrases that mark comment spam, one per line',
 			'lang_id'                                 => '(int) ID for language blog is written in',
 			'wga'                                     => '(array) Google Analytics Settings',
 			'disabled_likes'                          => '(bool) Are likes globally disabled (they can still be turned on per post)?',