Bumps VERSION to v0.4.0 in Quickstart

Signed-off-by: Daneyon Hansen <daneyon.hansen@solo.io>

Author: danehans

site-src/guides/index.md

@@ -74,7 +74,7 @@ This quickstart guide is intended for engineers familiar with k8s and model serv
 === "Latest Release"
 
       ```bash
-      VERSION=v0.3.0
+      VERSION=v0.4.0
       kubectl apply -f https://github.com/kubernetes-sigs/gateway-api-inference-extension/releases/download/$VERSION/manifests.yaml
       ```