CB-4281 send saveCredentials flag only if credentials exist

[devnaumov]

No description provided.

[Wroud]

probably we want to migrate DBAuthDialogController to hooks and use:

  let authModelId: string | null = null;

  if (connection.connectionInfo?.authNeeded || payload.resetCredentials) {
    authModelId = connection.connectionInfo?.authModel || driver?.defaultAuthModel || null;
  }

authModelId to determine when we requested user to enter database credentials and send config.credentials and config.saveCredentials only in this case