[service] [request] support parallel invocations on a single instance

One of our highly used Node.js lambdas is mostly IO-bound, waiting for a HTTP request to complete. It would be nice if a single lambda instance can handle multiple invocations in parallel, so we can save on start-up cost, have some shared cache and not run into our quota limit as fast (we're capped at 2500 at the moment, but it's not enough).

We'd use a regular Node.js service for this, but in this case we're using Lambda@edge so we're in a bind.

The specific lambda as a auth/acl check in cloudfront before we hit a S3 origin.

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Không có tệp repository, test hoặc entry point nào được nêu; hãy bắt đầu bằng cách kiểm tra xem repository roadmap này có chứa mã triển khai để xử lý các lần gọi Lambda@Edge hay không. Được xem là hoàn tất khi xác định và cung cấp hỗ trợ cho nhiều lần gọi đồng thời trên một instance, bao gồm hành vi và các ràng buộc cần thiết cho use case xác thực và CloudFront đã nêu.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.