code: func (cli *Client) PluginPush(ctx context.Context, name string, registryAuth string) (io.ReadCloser, error) {
  	headers := map[string][]string{"X-Registry-Auth": {registryAuth}}
  	resp, err := cli.post(ctx, "/plugins/"+name+"/push", nil, nil, headers)
  	if err != nil {
  		return nil, err
  	}
  	return resp.body, nil
  }
docs: // PluginPush pushes a plugin to a registry