feat: add links for testing

Author: ryan4yin

docs/other-usage-of-flakes/testing.md

@@ -6,4 +6,10 @@ TODO
 
 ## References
 
+- [Integration testing with NixOS virtual machines - nix.dev](https://nix.dev/tutorials/nixos/integration-testing-using-virtual-machines.html)
 - [NixOS Testing library](https://nixos.wiki/wiki/NixOS_Testing_library)
+- [Testing within NixOS - NixOS Manual](https://nixos.org/manual/nixos/stable/index.html#sec-nixos-tests)
+- [Testers - Nixpkgs Manual](https://nixos.org/manual/nixpkgs/unstable/#chap-testers)
+- [Unveiling the Power of the NixOS Integration Test Driver (Part 1)](https://nixcademy.com/2023/10/24/nixos-integration-tests/)
+- [Unveiling the Power of the NixOS Integration Test Driver (Part 2)](https://nixcademy.com/2023/12/01/nixos-integration-tests-part-2/)
+- [nix flake check - Nix Reference Manual](https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-flake-check)

docs/zh/other-usage-of-flakes/testing.md

@@ -6,4 +6,10 @@ TODO
 
 ## References
 
+- [Integration testing with NixOS virtual machines - nix.dev](https://nix.dev/tutorials/nixos/integration-testing-using-virtual-machines.html)
 - [NixOS Testing library](https://nixos.wiki/wiki/NixOS_Testing_library)
+- [Testing within NixOS - NixOS Manual](https://nixos.org/manual/nixos/stable/index.html#sec-nixos-tests)
+- [Testers - Nixpkgs Manual](https://nixos.org/manual/nixpkgs/unstable/#chap-testers)
+- [Unveiling the Power of the NixOS Integration Test Driver (Part 1)](https://nixcademy.com/2023/10/24/nixos-integration-tests/)
+- [Unveiling the Power of the NixOS Integration Test Driver (Part 2)](https://nixcademy.com/2023/12/01/nixos-integration-tests-part-2/)
+- [nix flake check - Nix Reference Manual](https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-flake-check)