fix incorrect term used

Author: mirrormx

content/get-started/workshop/03_updating_app.md

@@ -100,7 +100,7 @@ To remove a container, you first need to stop it. Once it has stopped, you can r
 
 ## Summary
 
-In this section, you learned how to update and rebuild a container, as well as how to stop and remove a container.
+In this section, you learned how to update and rebuild an image, as well as how to stop and remove a container.
 
 Related information:
  - [docker CLI reference](/reference/cli/docker/)