chore: added docker hub link to README

Author: evilsocket

README.md

@@ -17,6 +17,9 @@ Dreadnode command line interface
         <img alt="PyPI - Python Version" src="https://img.shields.io/pypi/pyversions/dreadnode-cli">
         <img alt="PyPI - Version" src="https://img.shields.io/pypi/v/dreadnode-cli">
     </a>
+    <a href="https://hub.docker.com/r/dreadnode/cli">
+        <img alt="Docker Hub" src="https://img.shields.io/docker/v/dreadnode/cli?logo=docker">
+    </a>
     <a href="https://github.com/dreadnode/cli/blob/main/LICENSE" target="_blank">
         <img alt="GitHub License" src="https://img.shields.io/github/license/dreadnode/cli">
     </a>