[skip ci] Add GitHub Actions badge in readme (#2931)

README.md

@@ -16,13 +16,15 @@
     <a href="#license-bsd-2-clause">License</a>
 </p>
 
-[![Build status](https://ci.appveyor.com/api/projects/status/ipa3ojgeaet1oko5?svg=true)](https://ci.appveyor.com/project/bkaradzic/bgfx)
+[![Appveyor CI](https://ci.appveyor.com/api/projects/status/ipa3ojgeaet1oko5?svg=true)](https://ci.appveyor.com/project/bkaradzic/bgfx)
+[![GitHub Actions](https://github.com/bkaradzic/bgfx/actions/workflows/main.yml/badge.svg)](https://github.com/bkaradzic/bgfx/actions)
 [![License](https://img.shields.io/badge/license-BSD--2%20clause-blue.svg)](https://bkaradzic.github.io/bgfx/license.html)
 [![Join the chat at https://discord.gg/9eMbv7J](https://img.shields.io/discord/712512073522872352?color=%237289DA&label=bgfx&logo=discord&logoColor=white)](https://discord.gg/9eMbv7J)
 
  * [GitHub Discussions](https://github.com/bkaradzic/bgfx/discussions)
  * [Discord Chat](https://discord.gg/9eMbv7J)
  * [AppVeyor CI](https://ci.appveyor.com/project/bkaradzic/bgfx)
+ * [GitHub Actions](https://github.com/bkaradzic/bgfx/actions)
 
 [What is it?](https://bkaradzic.github.io/bgfx/overview.html)
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