Fixes the Debugpy toolchain detection bug in #40324
When detecting what toolchain (venv) to use in the Debugpy configuration
stage, we used to only base it off of the current working directory
argument passed to the config. This is wrong behavior for cases like
mono repos, where the correct virtual environment to use is nested in
another folder.
This PR fixes this issue by adding the program and module fields as
fallbacks to check for virtual environments. We also added support for
program/module relative paths as well when cwd is not None.
Release Notes:
- debugger: Improve mono repo virtual environment detection with Debugpy
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Co-authored-by: Remco Smits <djsmits12@gmail.com>