[Feature request] python -m a.b , a new customized parameters $fileRelativeFullNameWithoutExt

**Is your feature request related to a problem? Please describe.**
I want to run a\b.py in current folder. default cmd is python -u a\b.py ,if a\b.py reference c.py, python cannot find module c.py.
use python -m a.b solved.

**Describe the solution you'd like**
Description of what you want to happen.
$fileRelativeFullNameWithoutExt represent relative path to workspaceRoot and replace path separator with dot