🦟 Bug fix

This fixes an issue with linking to python libraries on macOS.

Summary

When trying to update the homebrew bottles in osrf/homebrew-simulation#2036 so that python bindings can be used without setting the PYTHONPATH, I ran into the following error:

osrf/simulation/gz-math7:
  * python modules have explicit framework links
    These python extension modules were linked directly to a Python
    framework binary. They should be linked with -undefined dynamic_lookup
    instead of -lpython or -framework Python.
      /usr/local/opt/gz-math7/lib/python3.10/site-packages/gz/math.cpython-310-darwin.so
      /usr/local/opt/gz-math7/lib/python3.10/site-packages/ignition/math.cpython-310-darwin.so

I found that using MODULE instead of SHARED in our pybind11_add_module call fixes this issue.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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