sections-selector and index list appear to get their information from different sources

[bph-c8y]

There are two potential places to store an external link,

• content/sector_name/sector_name.md
• content/sector/sector_name/_index.md

e.g. for the REST API card,

• https://github.com/Cumulocity-IoT/c8y-docs/blob/develop/content/sector/rest_api/_index.md?plain=1
• https://github.com/Cumulocity-IoT/c8y-docs/blob/develop/content/rest_api/rest_api.md?plain=1

It appears that sections-selector gets the URL from a different location to the cards on index.html. To me, this is undesirable behaviour: you'd expect those two things to link to the same place, and you'd expect the same source of truth.

If you keep the same logic between index.html and sections-selector.html (i.e. #2783), this doesn't happen.

Is this intended, and should users be expected to keep those two links in sync?