Use a platform security rules reader instead of duplicating the code

See the note on RIGHTSAPI-1 about the architecture of this API.

There is a need for this API to read security rules set in XWiki , need which is already handled in XWiki by the security modules that implement the authorization API, but the way the need is answered is not enough for the needs of this API.
A proposal was made to make some changes in the security API to make that implementation suitable for the rights API needs: https://forum.xwiki.org/t/update-the-security-api-to-bring-it-closer-to-a-rights-api-implementation/7753 , but was not finalized before the first version of this extension, so we chose to duplicate that code in order to achieve the objective.

This task is about pushing that change and updating the Rights API to remove the duplicated code.