feat: lock the `nix build` to using the repo rust version

flake.lock

@@ -32,6 +32,22 @@
         "type": "indirect"
       }
     },
+    "nixpkgs-mozilla": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1744624473,
+        "narHash": "sha256-S6zT/w5SyAkJ//dYdjbrXgm+6Vkd/k7qqUl4WgZ6jjk=",
+        "owner": "mozilla",
+        "repo": "nixpkgs-mozilla",
+        "rev": "2292d4b35aa854e312ad2e95c4bb5c293656f21a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "mozilla",
+        "repo": "nixpkgs-mozilla",
+        "type": "github"
+      }
+    },
     "nixpkgs_2": {
       "locked": {
         "lastModified": 1722995383,
@@ -51,6 +67,7 @@
       "inputs": {
         "naersk": "naersk",
         "nixpkgs": "nixpkgs_2",
+        "nixpkgs-mozilla": "nixpkgs-mozilla",
         "utils": "utils"
       }
     },