[VecOps][NFC] Simplify Argsort docs
[VecOps][NFC] Simplify Argsort docs

Co-authored-by: Enrico Guiraud <81a634b61c6957bc62fe9d7d41b6d1b9a925da25@cern.ch>

olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root