pip Fails in Sandbox Mode

[abhisek]

When a non-existenant package is request, it correctly shows the error:

❯ pip install does-not-exists-338971
 Network   Failed to resolve the requested package version.
 → Check your network connection and try again.

But when a valid package is request, it fails with unknown error:

❯ pip install requests
 PackageManagerExecutionFailed   Package manager command exited with code: -1
 → Check the package manager command and its arguments

This likely means the sandbox is preventing the installation.

Likely related to #164