Unreleased dotenv run changes do not work on Windows

[MrSnapperVibes]

Commit 4543837 breaks the dotenv run command on Windows. If you enter the statement (for example) dotenv run -- python in Powershell there is no output. Subsequently entering $? reveals the last statement failed.

If I run python -c "import os; os.execvpe('python', ['python'], {})" I get the output FileNotFoundError: [Errno 2] No such file or directory: 'C:\\bin\\python'. I imagine this same error is occurring with the dotenv run command but the error message is getting lost.