Update nixpkgs

nix/sources.json

@@ -35,10 +35,10 @@
         "homepage": "",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "a44485a966bd24243fb8e7c36993d072a14b37a5",
-        "sha256": "1nzfw86gckzzl3il5lyk9xw1q3v8pzw1lisg271pg35ryj7clkbh",
+        "rev": "e8f6571c42b642ba7fd505c7348a3e70cf33e651",
+        "sha256": "0v5mhcgl08sd67g7icyshpx0fj9fr12bn6yxvpznij2rjid6n8lv",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/a44485a966bd24243fb8e7c36993d072a14b37a5.tar.gz",
+        "url": "https://github.com/NixOS/nixpkgs/archive/e8f6571c42b642ba7fd505c7348a3e70cf33e651.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "nixpkgs-21.05": {