Fix typo with docker command

README.md

@@ -53,7 +53,9 @@ It can be started using these commands:
 # In mesop-app-runner directory
 docker stop mesop-app-runner;
 docker rm mesop-app;
-docker build -t mesop-app-runner . && docker run --name mesop-app-runner -d -p 8080:8080 mesop-app-runner;
+docker build -t mesop-app-runner . && docker run --name mesop-app-runner \
+  -e MESOP_APP_RUNNER_TOKEN=your-secret-token \
+  -d -p 8080:8080 mesop-app-runner;
 ```
 
 ## Screenshots