[Chapel Merge] fix(makefile): support python 3.10

Branch: refs/heads/main
Revision: 369954e
Author: mppf
Link: fix(makefile): support python 3.10 by branchvincent · Pull Request #18857 · chapel-lang/chapel · GitHub
Log Message:

Merge pull request #18857 from branchvincent/python3.10

fix(makefile): support python 3.10

[PR by @branchvincent - thanks! Reviewed, tested, and merged by @mppf]

This fixes a bug detecting the current Python version, noticed when building with Python 3.10 in llvm@11, chapel: migrate to Python 3.10 by XuehaiPan · Pull Request #90708 · Homebrew/homebrew-core · GitHub

Before:

$ make -C third-party/chpl-venv test-venv PYTHON=python3.10
python3 version 3.5 or later is required to install chpldoc and start_test dependencies. See https://www.python.org/

After:

$ make -C third-party/chpl-venv test-venv PYTHON=python3.10
...
Successfully installed ...
Modified Files:
M third-party/chpl-venv/Makefile

Compare: https://github.com/chapel-lang/chapel/compare/04af2038c032...369954e88c2a