devel/py-setuptools_git_ls_files: add port: Python setuptools plugin to list all files tracked by git

setuptools_git_ls_files is a plugin for setuptools that finds all git tracked
files, including submodules.

WWW: https://github.com/anthrotype/setuptools_git_ls_files

PR: 270140
Reported by: Ting-Wei Lan <lantw44@gmail.com>