Revert conditional setting of stdin handle

[AceofSpades5757]

fixes #3374

I still like the change to avoid setting stdio if necessary, but it looks like this causes an issue on Windows.

After attempting other fixes, reverting the changes was the only thing that worked.

P.S. Conditional compilation could be added for non-Windows targets, but I think this would not add value to the codebase or Helix.

[AceofSpades5757]

Switched to conditional compilation and tested on Windows and Ubuntu (WSL). Everything seemed to work as intended.