cmake: Search Development.Module Python component to compile Python bindings (backport #840)

[mergify]

🦟 Bug fix

Fixes looking for Development cmake component of Python even if it was necessary.

Summary

CMake's FindPython offers two dev-related component of Python: Development.Module and Development.Embed (see https://cmake.org/cmake/help/latest/module/FindPython.html), or Development to search both. As gz-math is not embedding python, it only need Development.Module .

This is relevant in conda-forge since Python 3.15 split the files necessary for Development.Embed to suceed in libpython, so packages that only depend on python and do not embed python, need to only look for Development.Module, see conda-forge/gz-math-feedstock#46 (comment) .

Backport Policy

Development.Module requires CMake 3.18, so we can backport to any version that has a greater minimum CMake version.

• This is safe to backport to the following versions:
  • Jetty
  • Ionic
  • Harmonic
  • Fortress
• This should not be backported
• I am not sure
• Other (fill in yourself)

Checklist

• Signed all commits for DCO
• Added a screen capture or video to the PR description that demonstrates the fix (as needed)
• 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)
• Updated Bazel files (if adding new files). Created an issue otherwise.
• While waiting for a review on your PR, please help review another open pull request to support the maintainers
• Was GenAI used to generate this PR? If so, make sure to add "Assisted-by" to your commits. (See this policy for more info.)

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by and Generated-by messages.

Backports: If this is a backport, please use Rebase and Merge instead.

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This is an automatic backport of pull request #840 done by [Mergify](https://mergify.com).