Add guide for the Docker image

README.md

@@ -19,7 +19,15 @@ If you want to learn more about the extension, visit [How to Load Test Your Kafk
 - Support consumption from all partitions with a group ID
 - Support Kafka message compression: Gzip, Snappy, Lz4 & Zstd
 
-## Build
+## Run Using the Official Docker Image
+
+Since [v0.8.0](https://github.com/mostafa/xk6-kafka/releases/tag/v0.8.0) on, there is an [official Docker image](https://hub.docker.com/r/mostafamoradian/xk6-kafka) plus binaries in the assets. Before running your script, make sure to make it available to the container by mounting a volume (a directory) or passing it via stdin.
+
+```bash
+docker run --rm -i mostafamoradian/xk6-kafka:latest run - <scripts/test_json.js
+```
+
+## Build from Source
 
 The k6 binary can be built on various platforms, and each platform has its own set of requirements. The following shows how to build k6 binary with this extension on GNU/Linux distributions.