use Workers Assets based cache for the blog example (#558)

Author: vicb

examples/vercel-blog-starter/open-next.config.ts

@@ -1,6 +1,6 @@
 import { defineCloudflareConfig } from "@opennextjs/cloudflare";
-import kvIncrementalCache from "@opennextjs/cloudflare/overrides/incremental-cache/kv-incremental-cache";
+import staticAssetsIncrementalCache from "@opennextjs/cloudflare/overrides/incremental-cache/static-assets-incremental-cache";
 
 export default defineCloudflareConfig({
-  incrementalCache: kvIncrementalCache,
+  incrementalCache: staticAssetsIncrementalCache,
 });