fixup! Bump Haskell.nix to input-output-hk/haskell.nix#862 branch

Author: rvl

nix/sources.json

@@ -17,10 +17,10 @@
         "homepage": "https://input-output-hk.github.io/haskell.nix",
         "owner": "input-output-hk",
         "repo": "haskell.nix",
-        "rev": "dcdeb646dd7ee9b79c1b016df3e95959cf3c5479",
-        "sha256": "141fwgz03grp96byyl5p3ixvnxjxqii7mxw3s98579nznpa1wb46",
+        "rev": "8948fb8ba7ff08e3fd17b8813efe3a56f461b0d2",
+        "sha256": "0573vhh59al185h01pjdkhws8n7afs4z158k4mj7fvqdrpp6bp0z",
         "type": "tarball",
-        "url": "https://github.com/input-output-hk/haskell.nix/archive/dcdeb646dd7ee9b79c1b016df3e95959cf3c5479.tar.gz",
+        "url": "https://github.com/input-output-hk/haskell.nix/archive/8948fb8ba7ff08e3fd17b8813efe3a56f461b0d2.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "iohk-nix": {