In principle, the time spent by an applicant for a job interview does not have to be remunerated. The reason for this is that both parties have an interest in the interview. For domestic helpers, it is quite common for the employer to cover the travelling expenses to the interview.
If the applicant takes on the future tasks for a short time (e.g. one hour), this can be regarded as trial work. This only has to be paid if it has been agreed in advance. As work performed should always be remunerated, it seems appropriate to pay for the time spent. In the case of employment, for example, this can be done with the first salary.