Introduce hints

[nandorholozsnyak]

Is your feature request related to a problem? Please describe.
The properties can have extra hints.

https://docs.spring.io/spring-boot/docs/current/reference/html/configuration-metadata.html#appendix.configuration-metadata.format

Introduce them to the documentation.

[bhahn57570]

Is it planned to add the extra hint as part of the documentation ?

Currently using the description of properties is a workaround, but it is more accurate to place the possible values inside the hint section.