Fix security issues with the Trusted Publishing example

https://github.com/simonw/python-lib/blob/4b825ed/%7B%7Bcookiecutter.hyphenated%7D%7D/.github/workflows/publish.yml#L44-L49 suggests that building the dists within the same job that publishes them is okay. But it's not.
Such a structure opens the workflow users to privilege escalation through poisoning the build dependencies, which is why I've always insisted on the separation — the build scripts must never have access to id-token: write.

• https://packaging.python.org/en/latest/guides/publishing-package-distribution-releases-using-github-actions-ci-cd-workflows/
• https://docs.pypi.org/trusted-publishers/security-model/

Another suggestion is to fix the GitHub Environment name to represent the deployment target as it's meant to. I usually go for pypi and testpypi so it's obvious that uploading to both is separate.

I saw release here https://github.com/simonw/python-lib/blob/4b825ed/%7B%7Bcookiecutter.hyphenated%7D%7D/.github/workflows/publish.yml#L33C5-L33C25, which is not an upload target but a process name which is very generic.

The declaration syntax can also be extended to include a URL:

-     environment: release
+     environment:
+       name: pypi
+       url: https://pypi.org/project/{% endraw %}{{ cookiecutter.hyphenated }}{% raw %}/${{ github.ref_name }}

从 {{cookiecutter.hyphenated}}/.github/workflows/publish.yml 开始，重点查看第 33 行和第 44-49 行，然后阅读链接的 PyPI Trusted Publishing 指南。检查 build 和 publish 步骤如何共享权限，以及 release 环境是如何命名的。完成的标准是：workflow 将 build 与 publish 分开，使 build 脚本无法访问 id-token，并使用项目 URL 命名 PyPI 目标。