Taxonomy: Escape feed_image argument in Walker_Category::start_el().

See [11838] for the instance in `wp_list_authors()`.

Props abhijitrakas.
See #44880.
Built from https://develop.svn.wordpress.org/trunk@44413


git-svn-id: http://core.svn.wordpress.org/trunk@44243 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-walker-category.php

@@ -146,7 +146,7 @@ class Walker_Category extends Walker {
 			if ( empty( $args['feed_image'] ) ) {
 				$link .= $name;
 			} else {
-				$link .= "<img src='" . $args['feed_image'] . "'$alt" . ' />';
+				$link .= "<img src='" . esc_url( $args['feed_image'] ) . "'$alt" . ' />';
 			}
 			$link .= '</a>';