Coding Standards: Use strict comparison in `wp-includes/feed-atom-com…

…ments.php`.

Follow-up to [9818].

Props aristath, poena, afercia, SergeyBiryukov.
See #58831.

git-svn-id: https://develop.svn.wordpress.org/trunk@56324 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/feed-atom-comments.php

@@ -111,7 +111,7 @@
 
 		<?php
 		// Return comment threading information (https://www.ietf.org/rfc/rfc4685.txt).
-		if ( 0 == $comment->comment_parent ) : // This comment is top-level.
+		if ( '0' === $comment->comment_parent ) : // This comment is top-level.
 			?>
 			<thr:in-reply-to ref="<?php the_guid(); ?>" href="<?php the_permalink_rss(); ?>" type="<?php bloginfo_rss( 'html_type' ); ?>" />
 			<?php