Add callout for a common Docker Compose error

Author: nickjj

README.md

@@ -141,6 +141,10 @@ docker compose up --build
 Now that everything is built and running we can treat it like any other Rails
 app.
 
+Did you receive a `depends_on` "Additional property required is not allowed"
+error? Please update to at least Docker Compose v2.20.2+ or Docker Desktop
+4.22.0+.
+
 Did you receive an error about a port being in use? Chances are it's because
 something on your machine is already running on port 8000. Check out the docs
 in the `.env` file for the `DOCKER_WEB_PORT` variable to fix this.