How to remove the default tooltip?

## I'm submitting a...

[ ] Bug report  

[x ] Feature request

## Current behavior
When you put the pointer over the star group appear a "star-filled" tooltip. I wanna change it with 5 of 5 for example.

## Expected behavior

## Minimal reproduction of the problem with instructions

## Environment

Library version: X.Y.Z

Angular version: X.Y.Z


Browser:

- [ ] Chrome (desktop) version XX

No source file, test, or entry point is named. Start by locating where the star group's default tooltip is defined, then clarify whether the requested result is removing it or allowing custom text such as "5 of 5"; done means the selected tooltip behavior is configurable and covered by a reproducible check.

Written by the indexing model from the issue text.