Ensure alignment of Part 3 of CS API with Part 2 of EDR API

[ghobona]

OGC API - Environmental Data Retrieval - Part 2: Publish-Subscribe Workflow has been approved by the OGC Membership and will be released by the end of 2024.

The intention is to use Part 2 of the EDR API as the basis for a PubSub approach that is common to all OGC API Standards.

Therefore it is necessary to ensure that Part 3 of the CS API is consistent with Part 2 of the EDR API.

One of the changes needed will be updating the CS API to use AsyncAPI 3.0.0. There may be others, so a review is needed.

The Connected Systems SWG should review Part 2 of the EDR API and ensure that Part 3 of the CS API is aligned with Part 2 of the EDR API.

[alexrobin]

Discussed during 09/19 telecon.

The plan is:

• Implement "8. Requirements Class Publish-Subscribe (Pub/Sub)" as is
• Align with "9. Requirements Class Publish-Subscribe (Pub/Sub) Channels" (use HTTP API paths as channel IDs/topics)
• Cannot implement "10. Requirements Class Publish-Subscribe (Pub/Sub) Notification Message Payloads" as is. Suggest that fields (id, pubtime, operation) defined in this req class be separated from the GeoJSON requirement so it can be more easily reused.

Final decisions will be made when writing part 3.