Adjust message

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: swissspidy

src/Core_Command.php

@@ -1666,7 +1666,7 @@ private function cleanup_old_files() {
 		if ( $count ) {
 			WP_CLI::log( number_format( $count ) . ' files cleaned up.' );
 		} else {
-			WP_CLI::log( 'No files found that need cleaning up.' );
+			WP_CLI::log( 'No old files were removed.' );
 		}
 	}