Styles created multiple times when using function values

__Expected behavior:__
Duplicate styles shouldn't be created.

__Describe the bug:__
On every component render, in which useStyles prop changes, new duplicate styles are created. I've managed to reproduce the bug in Codesandbox. To see it:

1. Open codesandbox link from below
2. Inspect red text element and see styles applied
3. Click on button few times to cause component re-render
4. Inspect some another element on the page and the red text again.
5. Notice duplicate styles
The styles are duplicated only for elements styled with css selector. If you check styles on the element with container class, you'll see there is no duplication there.

__Codesandbox link:__
https://codesandbox.io/s/react-jss-playground-7ftrs?file=/index.js

__Versions (please complete the following information):__
- jss: 10.1.1
- Browser [e.g. chrome, safari]: any
- OS [e.g. Windows, macOS]: any