Bump pyinstaller version

[mmerklinger]

This PR raises the required version for pyinstaller. With the new version the installation process with Python 3.12 works too. Quick testing of some features didn't show any other incompatibilities with Python 3.12. Hence I also added the respective classifier.

Changes

• Update pyinstaller to ~= 6.5.0.
• Add Python 3.12 classifier.

Checklist

Make sure to run make check and make fix before creating a PR, otherwise the CI will fail.

• [x] tested with Python3.9
• [x] signed commits
• [ ] updated documentation (e.g. parameter description, inline doc, docs.nitrokey)
• [ ] added labels

Test Environment and Execution

• OS:
• device's model:
• device's firmware version:

Relevant Output Example

Fixes #