@id title expo fix (#218)

* Update date type to EDTF in acquisition date mapping

Changed "@type" from "Periode" to EDTF in the mapping logic to accurately reflect the expected data type. This ensures compatibility with the EDTF standard for representing date information.

* Comment out unused identifier construction logic

The construction of the `@id` field in the tentoonstellingMapper was commented out as it was not used. This change helps streamline the code and avoids unnecessary generation of unused data.