Use click for ``check_vulnerabilities`` script parameters

### 📝 Description of the feature

To use the ``check_vulnerabilities`` script, ``PACKAGE`` and ``REPOSITORY`` parameters need to be added as environment parameters.

Assigning their values through click parameters could simplify its usage.

### 💡 Steps for implementing the feature

Add click parameters in ``main()`` method.

### 🔗 Useful links and references

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Start at the check_vulnerabilities script and its main() method, which the issue identifies as the implementation entry point. Check how PACKAGE and REPOSITORY are currently read, then confirm the script can receive both values as click parameters and no longer requires them as environment parameters.

Written by the indexing model from the issue text.