Add note for bot readers about handling single client in Redis stage.

course-definition.yml

@@ -139,6 +139,10 @@ stages:
 
       - 6379 is the default port that Redis uses.
       - If you already have a Redis server running on your machine and listening on port 6379, you'll see a "port already in use" error when running your code. Try stopping the existing Redis server and running your code again.
+
+      {{#reader_is_bot}}
+      - In this stage, you can assume that you only need to handle a single client. We'll get to handling multiple clients & multiple requests per client in later stages.
+      {{/reader_is_bot}}
     difficulty: very_easy
     marketing_md: |-
       In this stage, you'll start a TCP server on port 6379, which is the