Python Debugger - using python in interactive mode via PYTHONINSPECT #5497

Issue Type: Bug

It looks like the VS Code does not correctly handle the PYTHONINSPECT environment variable (equivalent of doing python.exe -i)

testing.py

a = 2

launch.json

    {
        "name": "vtest",
        "type": "python",
        "request": "launch",
        "program": "${file}",
        "console": "integratedTerminal",
        "env": {
            "PYTHONINSPECT": "equivalent of python.exe -i"
        },
        "cwd": "${workspaceRoot}",
    }

Using that debugger to debug testing.py, you'll see that the interactive mode launches. If you type 1+1 in that REPL you get 2 back. But if you type 'a' to get 2, you get a stdin error like below:

Extension version: 2019.4.11987
VS Code version: Code 1.33.1 (51b0b28134d51361cf996d2f0a1c698247aeabd8, 2019-04-11T08:27:14.102Z)
OS version: Windows_NT x64 10.0.17763