docs(guide): add WebSockets to requirements

Author: jsjoeio

docs/guide.md

@@ -45,6 +45,10 @@ For a good experience, we recommend at least:
 
 You can use whatever linux distribution floats your boat but in this guide we assume Debian on Google Cloud.
 
+In order to work properly, your enviornment should have the following enabled:
+
+- WebSockets (used to communicate between code-server client and server)
+
 ### Google Cloud
 
 For demonstration purposes, this guide assumes you're using a VM on GCP but you should be