Placeholder for last change to the pin

Description of the request:

The customer would like a new placeholder {{pin-last-modified-date}}, which represents the last modification date of a pin in the report - analogous to the already existing {{pin-creation-date}} for the creation date.

Background:

During ongoing maintenance, the documentation is continuously updated in the same pin. However, only the original creation date appears in the report, which can falsely give the impression that nothing has happened since then.

Added value:

• Correct display of the current processing status

• Traceability of maintenance intervals

• Relevance for all use cases with ongoing documentation in the same pin