chore: WP_Term_Query::get_terms should return a numeric string when counting

Author: justlevine

src/wp-includes/class-wp-term-query.php

@@ -431,7 +431,7 @@ public function get_terms() {
 
 			if ( ! $in_hierarchy ) {
 				if ( 'count' === $args['fields'] ) {
-					return 0;
+					return '0';
 				} else {
 					$this->terms = array();
 					return $this->terms;