feat: allow extractor to receive mutable requests

[DDtKey]

Description:

These are backward compatible changes to allow the permission extractor to receive mutable ServiceRequest.

Checklist:

• [X] Tests for the changes have been added (for bug fixes / features);
• [ ] Docs have been added / updated (for bug fixes / features).
• [X] This PR has been added to CHANGELOG.md (to [Unreleased] section);

Closes #16