Remove redundant contributors badge

Author: vyahello

README.md

@@ -1,10 +1,9 @@
 [![made-with-python](https://img.shields.io/badge/Made%20with-Python-1f425f.svg)](https://www.python.org/)
 [![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
 [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
-[![GitHub contributors](https://img.shields.io/github/contributors/vyahello/python-optimization-cheetsheet.svg)](https://GitHub.com/vyahello/python-optimization-cheetsheet/graphs/contributors/)
 
 # Python optimization cheetsheet
-Implementation of python optimization cheetsheet (`yield`, `generators`, `coroutines` and `asyncio`). Source code located [here](materials).
+Implementation of python optimization cheetsheet (`yield`, `generators`, `coroutines` and `asyncio`). The source code is located [here](materials).
 
 **Tools**
 - python 3.6, 3.7, 3.8