added docker badge

Author: THEGOLDENPRO

README.md

@@ -4,6 +4,8 @@
 
   <sub>Behold the **anime girls holding programming books** API!</sub>
 
+  [![Docker Badge](https://img.shields.io/docker/v/devgoldy/aghpb_api?label=docker)](https://hub.docker.com/r/devgoldy/aghpb_api "We're on docker!")
+
 </div>
 
 This is an API I made for the anime girls holding programming books [github repo](https://github.com/cat-milk/Anime-Girls-Holding-Programming-Books) because I was bored.