code: private boolean subModuleExists(File dir) {
          if (isSlotDirectory(dir)) {
              return true;
          } else {
              File[] children = dir.listFiles(File::isDirectory);
              for (File child : children) {
                  if (subModuleExists(child)) {
                      return true;
                  }
              }
          }
  
          return false;
      }
docs: depth- first search for any module - just to check that the suggestion has any chance of delivering correct result