chore: updated pytest badge in README (#863)

The library does support pytest v8, this is also highlighted in the table in the README

README.md

@@ -4,7 +4,7 @@
 
 [![All Contributors](https://img.shields.io/badge/all_contributors-2-orange.svg?style=flat-square)](#contributors) [![Maturity badge - level 4](https://img.shields.io/badge/Maturity-Level%204%20--%20Critical-brightgreen.svg)](https://github.com/tophat/getting-started/blob/master/scorecard.md) [![Stage](https://img.shields.io/pypi/status/syrupy)](https://pypi.org/project/syrupy/) [![Discord](https://img.shields.io/discord/809577721751142410?label=community%20chat)](https://discord.gg/YhK3GFcZrk)
 
-![Pytest>=5.1.0,<8.0.0](https://img.shields.io/badge/pytest-%3E%3D5.1.0,%20%3C8.0.0-green) [![Pypi](https://img.shields.io/pypi/v/syrupy)](https://pypi.org/project/syrupy/) [![Wheel](https://img.shields.io/pypi/wheel/syrupy)](https://pypi.org/project/syrupy/) ![PyPI - Python Version](https://img.shields.io/pypi/pyversions/syrupy) [![PyPI - Downloads](https://img.shields.io/pypi/dm/syrupy)](https://pypi.org/project/syrupy/) [![PyPI - License](https://img.shields.io/pypi/l/syrupy)](./LICENSE)
+![Pytest>=5.1.0,<9.0.0](https://img.shields.io/badge/pytest-%3E%3D5.1.0,%20%3C9.0.0-green) [![Pypi](https://img.shields.io/pypi/v/syrupy)](https://pypi.org/project/syrupy/) [![Wheel](https://img.shields.io/pypi/wheel/syrupy)](https://pypi.org/project/syrupy/) ![PyPI - Python Version](https://img.shields.io/pypi/pyversions/syrupy) [![PyPI - Downloads](https://img.shields.io/pypi/dm/syrupy)](https://pypi.org/project/syrupy/) [![PyPI - License](https://img.shields.io/pypi/l/syrupy)](./LICENSE)
 
 ![Build Status](https://github.com/tophat/syrupy/workflows/Syrupy%20CICD/badge.svg) [![codecov](https://codecov.io/gh/tophat/syrupy/branch/main/graph/badge.svg)](https://codecov.io/gh/tophat/syrupy)