code: func UpdateConfig(tx Tx, c *api.Config) error {
  	// Ensure the name is either not in use or already used by this same Config.
  	if existing := tx.lookup(tableConfig, indexName, strings.ToLower(c.Spec.Annotations.Name)); existing != nil {
  		if existing.GetID() != c.ID {
  			return ErrNameConflict
  		}
  	}
  
  	return tx.update(tableConfig, c)
  }
docs: // UpdateConfig updates an existing config in the store.
  // Returns ErrNotExist if the config doesn't exist.