ci: Use Python virtual environment in "x86_64-macos-native" job

[hebasto]

Fixes #1768.

This PR explicitly sets up a virtual environment instead of using uv, as suggested here, for the following reasons:

1. It does not require granting a third-party action access to the repository.
2. This approach is already used in other parts of the CI framework (it’s unclear why it was missed in Fix symbol visibility issues, add test for it #1359 in the first place).

[real-or-random]

utACK d3ae054

Let's wait for green.

Thanks for fixing CI so quickly. :)

I agree, that's simpler and does the job. I still think uv is a good idea for devs who want to run the script locally, but that's a different story then.

[real-or-random]

ACK f252da7