nixpkgs: bumped to the HEAD of 20.09

nix/sources.json

@@ -54,10 +54,10 @@
         "homepage": "https://github.com/NixOS/nixpkgs",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "52090c613ad854abb824dcbba20e19bfa3890e91",
-        "sha256": "08ckikizpya76b1vmaglkh4aqh661h3r2qzss69106amqmvwl9i6",
+        "rev": "eae0cabc124702e04bb2098070ca46d661543d29",
+        "sha256": "1xbhy14agzjyb8mcnzi6ii535rig2fhq3h3zdfdv1kg2443sj6vd",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/52090c613ad854abb824dcbba20e19bfa3890e91.tar.gz",
+        "url": "https://github.com/NixOS/nixpkgs/archive/eae0cabc124702e04bb2098070ca46d661543d29.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     }
 }