Python version not matching with the system

Both on the flatpak version of vscode and code-oss, with and without virtualenv, Python would use version 3.9.9, while the Python version of the OS I'm using (pop_OS!) is 3.10.4

This led to the inability of using the PyLance/Intellisense extensions. Actually the whole terminal shell inside vscode was pretty weird... since the python version is wrong, pip was also unusable, even directly using the binaries.

I also found other people from [stackoverflow](https://stackoverflow.com/questions/70817824/visual-studio-code-using-wrong-python-version-correct-version-does-not-show-up) with the same issue. Sorry if I missed anything or if this is already an open issue.

No source file, test, or entry point is named. Reproduce the issue in the Flatpak versions of VS Code and code-oss on Pop!_OS, comparing Python 3.9.9 with the system's Python 3.10.4 and checking how the integrated terminal, virtualenv, and pip resolve them. Done means the cause is identified and the expected Python and pip behavior is restored or clearly documented.

索引モデルが issue の本文から書いたものです。