mac ci: Make PATH invariant to installed Python version

[kazarmy]

Your checklist for this pull request

• I've read the guidelines for contributing to this repository
• I made sure to follow the project's coding style
• I've documented or updated the documentation of every function and struct this PR changes. If not so I've explained why.
• I've added tests that prove my fix is effective or that my feature works (if possible)
• I've updated the rizin book with the relevant information (if needed)

Detailed description

This pr makes the exported PATH in the Mac CI build be invariant to the installed Python version, meaning that it doesn't need to be updated if a Python version > 3.13 is installed.

Test plan

All builds are green.

Closing issues

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