Adapt requirements in section 5.4.5 Discovery of Catalog Services

[lgblaumeiser]

The current formulation is:
In that case, the Participant MUST add an entry to the DID document's service array adhering to the corresponding JSON schema.

As within the Catena-X dataspace this DID document entry cannot be used in its current form due to not enough information provided by the path information. Therefore, I propose to change the MUST to a SHOULD or MAY.

Reasoning: The current mechanism is from how I see the situation not complex enough to handle multi dataspace, multi version scenarios. Why is every dataspace forced to provide this entry in the DID document, even if the dataspace designer have a more innovative approach to solve the issue.

[arnoweiss]

Discussion resolved with #169