async isDisabled(retryInterval, retryTimeout) {
    const elem = await firstElement.apply(this, [retryInterval, retryTimeout]);
    return await elem.isDisabled();
  }
@description Checks if element is disabled
@param {number} retryInterval Retry Interval in milliseconds (defaults to global settings).
@param {number} retryTimeout Retry Timeout in milliseconds (defaults to global settings).
@returns {boolean} true if disabled, else false.