Load checks from all yaml files in the specified directories.

def LoadChecksFromDirs(dir_paths, overwrite_if_exists=True):
  """Load checks from all yaml files in the specified directories."""
  loaded = []
  for dir_path in dir_paths:
    cfg_files = glob.glob(os.path.join(dir_path, "*.yaml"))
    loaded.extend(LoadChecksFromFiles(cfg_files, overwrite_if_exists))
  return loaded