wp_delete_file_from_directory( string $file, string $directory )

function wp_delete_file_from_directory( $file, $directory ) {
	$real_file = realpath( wp_normalize_path( $file ) );
	$real_directory = realpath( wp_normalize_path( $directory ) );

	if ( false === $real_file || false === $real_directory || strpos( wp_normalize_path( $real_file ), trailingslashit( wp_normalize_path( $real_directory ) ) ) !== 0 ) {
		return false;
	}

	wp_delete_file( $file );

	return true;
}