Accept artifact dir as argument in post_mlinter_review.py (#48106)
Accept artifact dir as sys.argv[1] in post_mlinter_review.py
Follow-up to #48088 which passes the path via MLINTER_FINDINGS_DIR but
the script was still looking in CWD.
Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>