Add support for activating env created using microvenv

[TylerLeonhardt]

Testing #21100

After following the steps in #21100 I tried running python in a new terminal inside of VS Code and got:\

codeuser@DESKTOP-HOME:~/test$ python -m pip install pytest
Command 'python' not found, did you mean:
  command 'python3' from deb python3
  command 'python' from deb python-is-python3

Not much in the logs department:

2023-04-25 12:23:40.485 [info] Experiment 'pythonPromptNewFormatterExt' is active
2023-04-25 12:23:40.485 [info] Experiment 'pythonPromptNewToolsExt' is active
2023-04-25 12:23:40.538 [info] Test server listening.
2023-04-25 12:23:40.547 [info] Python interpreter path: ./.venv/bin/python
2023-04-25 12:23:41.702 [info] Starting Pylance language server.

This was in WSL using WSLg so here's what the PATH looks like:

/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/lib/wsl/lib:/mnt/c/Python310/Scripts/:/mnt/c/Python310/:/mnt/c/Program Files (x86)/Microsoft SDKs/Azure/CLI2/wbin:/mnt/c/Windows/system32:/mnt/c/Windows:/mnt/c/Windows/System32/Wbem:/mnt/c/Windows/System32/WindowsPowerShell/v1.0/:/mnt/c/Program Files (x86)/ATI Technologies/ATI.ACE/Core-Static:/mnt/c/ProgramData/chocolatey/bin:/mnt/c/Program Files/PowerShell/7-preview/preview:/mnt/c/Program Files (x86)/Yarn/bin/:/mnt/c/Program Files/OpenSSH-Win64:/mnt/c/Users/Tyler/Downloads/Storage_Download:/mnt/c/images/kahuku/14.26.1/Storage_Download:/mnt/c/Program Files/nodejs/:/mnt/c/Program Files/Git/cmd:/mnt/c/Program Files/Docker/Docker/resources/bin:/mnt/c/Program Files (x86)/GnuPG/bin:/mnt/c/Users/tyleonha/AppData/Local/Microsoft/WindowsApps:/mnt/c/Users/tyleonha/AppData/Local/Programs/Microsoft VS Code Insiders/bin:/snap/bin

[karthiknadig]

@karrtikr Not sure why the PATH to the new venv is not being selected.

[karrtikr]

@karthiknadig,

• How are we making sure the environment is activated in terminal?
• And what is the path of environment that is used to create the env?

[karthiknadig]

The environment after certation is selected. It is no different than a venv. This is microvenv, there are no activate scripts. All that is needed is that python points to .venv/bin/python

[karrtikr]

Well, currently activation requires activation scripts. If there're no scripts no env is activated.

[karthiknadig]

@karrtikr microvenv does not use activation to work. All it needs is to be on PATH. When we detect a microvenv (i.e, no activation scripts, but has pyenv.cfg), then all that is needed is to add the bin path (i.e, .venv/bin) to PATH.