docs: fix incorrect proxy-defaults config in Lua Envoy extension (#18418)

fix incorrect proxy-defaults config

website/content/docs/connect/proxies/envoy-extensions/usage/lua.mdx

@@ -44,13 +44,15 @@ The following example configures the Lua Envoy extension on every service by usi
 ```hcl
 Kind = "proxy-defaults"
 Name = "global"
-Protocol = "http"
+Config {
+  protocol = "http"
+}
 EnvoyExtensions {
   Name = "builtin/lua"
   Arguments = {
     ProxyType = "connect-proxy"
     Listener  = "inbound"
-    Script    = <<-EOS
+    Script    = <<-EOF
 function envoy_on_request(request_handle)
   meta = request_handle:streamInfo():dynamicMetadata()
   m = meta:get("consul")
@@ -59,7 +61,7 @@ function envoy_on_request(request_handle)
   request_handle:headers():add("x-consul-datacenter", m["datacenter"])
   request_handle:headers():add("x-consul-trust-domain", m["trust-domain"])
 end
-EOS
+ EOF
   }
 }
 ```