Add ignore comment on valid user input usage

Co-authored-by: Kelly Dwan <[email protected]>

source/wp-content/themes/wporg-developer-2023/src/dashicons-page/render.php

@@ -21,7 +21,7 @@
 	$icons_sections[] = $icon_section;
 }
 
-$selected_icon = $_GET['icon'] ?? '';
+$selected_icon = $_GET['icon'] ?? ''; // phpcs:ignore WordPress.Security.ValidatedSanitizedInput -- Value checked against icon safelist.
 if ( ! array_key_exists( $selected_icon, $icons ) ) {
 	$selected_icon = array_rand( $icons );
 }