Make public fields linked with documentation. (#3678)
Make public fields linked with documentation. (#3678)

Motivation:

The public fields are not included by `ApiIndexTask`.

Modifications:

- Add `.field-details` to the CSS selector used for selecting public
  APIs.

Result:

We can link public fields in the documentation.
For example:
```
<type://HttpStatus#NO_CONTENT>
```
trustin/armeria,kojilin/armeria,minwoox/armeria,kojilin/armeria,line/armeria,kojilin/armeria,line/armeria,minwoox/armeria,line/armeria,line/armeria,trustin/armeria,minwoox/armeria,minwoox/armeria,line/armeria,minwoox/armeria,kojilin/armeria,trustin/armeria,kojilin/armeria,minwoox/armeria,trustin/armeria,line/armeria,trustin/armeria,trustin/armeria,kojilin/armeria