Issue description

I cannot run pipenv check --scan. Every time I try, it fails after attempting to install safety.

Expected result

pipenv check --scan should run successfully and report vulnerabilities.

Actual result

Output when running the command:

Steps to replicate

1. Run pipenv check --scan
2. Accept the prompt to install safety
3. The installation succeeds, but running still fails with module not found.

Pipenv support info

(Please run $ pipenv --support and paste results here)