Add another API Spec field in informational meeting

When a service/product is onboarding, we ask them for a link to their REST API spec for management and data plane.
In the Scheduler tool, we are only asking for an API Spec, without knowing which type it is.
After talking to @ladonnaq we agreed on modifying the Informational meeting and Add an extra field for api spec and make the disctintion between the 2 types.

Once this is done, we can update the `triage` work item with the respective PRs.

Start in the Scheduler tool by locating the Informational meeting entry and its existing API Spec field. Confirm how the meeting data is consumed by the triage work item. Done means the meeting distinguishes management-plane and data-plane API specs and provides the respective information for triage.

Written by the indexing model from the issue text.