Python version in unit test not updated

Hey it seems that the configuration in Github's CI test is hard coded, and does not take into account the version chosen when initializing the repo. We had to change it manually.

```yml
unit_tests:
    needs: [linting]
    runs-on: ${{ matrix.platform }}
    strategy:
      max-parallel: 4
      matrix:
        platform: [ubuntu-latest, macos-latest]
        python-version: ["3.12"]
```