Verify ASCII write is enabled

This endpoint returns whether DATEV's Lohnimportdatenservice is enabled, which is the service required to submit ASCII files. It works for both DATEV HR and DATEV LAUDS integrations.

<Note>This check says nothing about JSON writes through the LAUDS API. Those go through the Lohnaustauschdatenservice that every DATEV LAUDS integration connects with, so they are always available on DATEV LAUDS.</Note>