Coding Standards: Replace an empty foreach loop in wp_replace_in_html_tags().

This aims to clarify the intention of the code and improve readability.

Follow-up to [33359].

Props jrf, TobiasBg, mi5t4n, dhruvang21, mayura8991, nadimcse, Presskopp, SergeyBiryukov.
Fixes #61860.

git-svn-id: https://develop.svn.wordpress.org/trunk@58889 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-includes/formatting.php

@@ -762,8 +762,8 @@ function wp_replace_in_html_tags( $haystack, $replace_pairs ) {
 	// Optimize when searching for one item.
 	if ( 1 === count( $replace_pairs ) ) {
 		// Extract $needle and $replace.
-		foreach ( $replace_pairs as $needle => $replace ) {
-		}
+		$needle  = array_key_first( $replace_pairs );
+		$replace = $replace_pairs[ $needle ];
 
 		// Loop through delimiters (elements) only.
 		for ( $i = 1, $c = count( $textarr ); $i < $c; $i += 2 ) {