Adding docker pulls counter badge

README.md

@@ -1,5 +1,8 @@
 #  changedetection.io
 ![changedetection.io](https://github.com/dgtlmoon/changedetection.io/actions/workflows/python-app.yml/badge.svg?branch=master)
+<a href="https://hub.docker.com/r/dgtlmoon/changedetection.io" target="_blank" title="Docker Pulls">
+<img src="https://img.shields.io/docker/pulls/dgtlmoon/changedetection.io" alt="Docker Pulls"/>
+</a>
 
 ## Self-hosted change monitoring of web pages.