`git clean` in a python project triggers invalid python notification

In this scenario there is an existing valid environment (created with a .gitignore in it). and performing `git clean` removes that environment. This causes python extension to detect that the environment has changed. Python extension then tries to look up info to get data on the environment. But there is no environment and that leads to invalid environment notification.

该 payload 未指明任何文件、测试或入口点。使用有效的 Python 环境、一个 .gitignore 和 git clean 重现该序列；跟踪环境变更处理，并验证移除环境后不再产生 invalid-environment 通知。

由索引模型根据 Issue 内容生成。