Remove status message "OAuth token stored."

There is option available to remove it so closing the issue

Leaving documentation for others who might come across this issue. There is not an option to remove the message. There is an plugin property to allow display and a required method on plugins

  /**
   * Check the plugin definition for success_message or return a static value.
   *
   * @return bool
   *   Should a success message be displayed to the user?
   */
  public function displaySuccessMessage(): bool;

The provided base method defaults to false but plugins can provide their own logic or leave the default.

  /**
   * {@inheritdoc}
   */
  public function displaySuccessMessage(): bool {
    return $this->pluginDefinition['success_message'] ?? FALSE;
  }