Update README.md

Author: SSARCandy

README.md

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 # Coherent Line Drawing
 
+[![C/C++ CI](https://github.com/SSARCandy/Coherent-Line-Drawing/workflows/C/C++%20CI/badge.svg)](https://github.com/SSARCandy/Coherent-Line-Drawing/actions)
 [![Build Status](https://travis-ci.org/SSARCandy/Coherent-Line-Drawing.svg?branch=master)](https://travis-ci.org/SSARCandy/Coherent-Line-Drawing)
 [![codecov](https://codecov.io/gh/SSARCandy/Coherent-Line-Drawing/branch/master/graph/badge.svg)](https://codecov.io/gh/SSARCandy/Coherent-Line-Drawing)
 [![License: MIT](https://img.shields.io/badge/License-MIT-green.svg)](https://github.com/SSARCandy/Coherent-Line-Drawing/blob/master/LICENSE)