update to use start-containers.sh

Author: jeremyplichta

samples/bookstore-demo/README.md

@@ -15,8 +15,8 @@ If you want to run the whole thing within docker (the project itself as well as
 # ensure you have maven if needed
 # brew install maven
 
-mvn package
-docker compose up
+# build and start containers
+./start-containers.sh
 ```
 
 ### Remotely
@@ -65,4 +65,4 @@ After which you may run the app either directly from your IDE or as a simple jar
 ```shell
 mvn package
 java -jar target/test-sessions-0.0.1-SNAPSHOT.jar --spring.profiles.active=docker
-```
+```