[Model Update]: Digital Product Passport for Rel 24.08

[catroest]

Update Reason

• update of descriptions and typos
• add optional attributes for last modification and other operators of the DPP

MS1 Criteria

• [x] The model that should be updated exists
• [x] The referenced use case exists
• [x] The potential updates are discussed with all stakeholders
• [x] A decision on versioning was made in consensus with the affected parties according to the guidelines.
• [ ] The potential update will be either
  • [ ] backward compatible or
  • [x] a (chain of) migration strategy(-ies) from all non-deprecated previous versions to the new model will be developed
• [x] A modeling steward has been assigned