Option to prepare & print path to the virtualenv to be used

[tanavamsikrishna]

This is within the context of using pipx run

While editing a local script in an IDE, the path to the virtualenv or python needs to be provided (for linting & autocompletions).
The virtualenv needs to have the dependencies installed as it is not a typical pyproject.toml or setup.py based project, and thus cannot be managed by IDEs.

Proposed idea:

1. Add a new flag --print-python-path to pipx run
2. Check if this flag is set in the function pipx.commands.run.run_script and skip calling any exec_app but instead print the path to python executable (to stdout) and exit

(The above idea is inspired by rust-script's --package option)

Alternatives:

• Print a parsable output for --verbose option and add --dry-run option.