[Fixes #12512] Expose publish, approval and feature permissions inside PermissionLevelMixin

[mattiagiupponi]

review https://github.com/GeoNode/geonode/pull/12515 first then change the base branch of this PR to master

Checklist

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 86.61417% with 17 lines in your changes missing coverage. Please review.

Project coverage is 64.22%. Comparing base (9235048) to head (4e44e69). Report is 2 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #12516 +/- ## ========================================== + Coverage 64.18% 64.22% +0.03% ========================================== Files 888 888 Lines 53502 53551 +49 Branches 6599 6605 +6 ========================================== + Hits 34340 34392 +52 + Misses 17652 17650 -2 + Partials 1510 1509 -1 ```