fix: Adding Custom Cache Mirrors

docs/nixos-with-flakes/nixos-with-flakes-enabled.md

@@ -267,7 +267,7 @@ To customize the cache source, we must add the related configuration in `flake.n
 }
 ```
 
-After adding the new substituters, it still won't take effect. In this case, when directly deploying the configuration, you'll encounter the following error:
+After adding the new substituters, it still won't take effect. In this case, when directly deploying the configuration, you'll encounter the following warnings:
 
 ```
 ...

docs/zh/nixos-with-flakes/nixos-with-flakes-enabled.md

@@ -251,7 +251,7 @@ Nix 为了加快包构建速度，提供了 <https://cache.nixos.org> 提前缓
 }
 ```
 
-添加完新 substituters 后，它仍然不会失效，这时直接部署配置，会这个报错：
+添加完新 substituters 后，它仍然不会失效，这时直接部署配置，会出现这个 warning：
 
 ```
 ...