Update build status badge

Move from Travis to GitHub actions

Author: fpistm

README.md

@@ -2,7 +2,8 @@
 [![GitHub release](https://img.shields.io/github/release/stm32duino/Arduino_Core_STM32.svg)](https://github.com/stm32duino/Arduino_Core_STM32/releases/latest)
 ![GitHub All Releases](https://img.shields.io/github/downloads/stm32duino/Arduino_Core_STM32/total.svg?label=downloads%20since%201.4.0)
 [![GitHub commits](https://img.shields.io/github/commits-since/stm32duino/Arduino_Core_STM32/1.8.0.svg)](https://github.com/stm32duino/Arduino_Core_STM32/compare/1.8.0...master)
-[![Build Status](https://travis-ci.com/stm32duino/Arduino_Core_STM32.svg?branch=master)](https://travis-ci.com/stm32duino/Arduino_Core_STM32)
+<!-- [![Build Status](https://travis-ci.com/stm32duino/Arduino_Core_STM32.svg?branch=master)](https://travis-ci.com/stm32duino/Arduino_Core_STM32) -->
+![STM32 Core Continuous Integration](https://github.com/stm32duino/Arduino_Core_STM32/workflows/STM32%20Core%20Continuous%20Integration/badge.svg)
 
 * [Introduction](https://github.com/stm32duino/Arduino_Core_STM32#Introduction)<br>
 * [Getting Started](https://github.com/stm32duino/Arduino_Core_STM32#getting-started)<br>