Consider adding a section "6.1.5 Candidate Jakarta Technlogies"

Following the [discussion on the mailing list](https://www.eclipse.org/lists/jakartaee-platform-dev/msg04136.html) regarding adding specifications, would it make sense to add a section listing candidate specifications?

* list specifications that could be candidates for inclusion in a future release
* **not the same as optional**
* no requirement to implement
* no promise that it will be included at any time
* just for informational purposes (a heads-up if you like)

[AB#167](https://dev.azure.com/jakarta-ee-azdo/7cf9a9d3-9854-41e0-9a66-99506a9ed874/_workitems/edit/167)