Add benchmark script (#666)

test/benchmark/tests/burst-load/sample.js

@@ -0,0 +1,17 @@
+import http from "k6/http";
+import { check } from "k6";
+
+export let options = {
+    stages: [
+        { duration: "15s", target: 10 },
+        { duration: "45s", target: 500  },
+    ]
+};
+
+export default function() {
+    let params = { timeout: 30 }
+    let res = http.get(`${__ENV.FN_ENDPOINT}`)
+    check(res, {
+        "status is 200": (r) => r.status === 200
+    });
+};