niv nixops: update ed2868fb -> 1239ff7f (#2618)

## Changelog for nixops:
Branch: master
Commits: [NixOS/nixops@ed2868fb...1239ff7f](NixOS/nixops@ed2868f...1239ff7)

* [`cad5d0c1`](NixOS/nixops@cad5d0c) Fixes a missing key error for attrs

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

nix/sources.json

@@ -82,10 +82,10 @@
         "homepage": "https://nixos.org/nixops",
         "owner": "NixOS",
         "repo": "nixops",
-        "rev": "ed2868fbc0b5924fcd4a60a8bd32a14fa196381b",
-        "sha256": "14av9x7i3fvnzmx711x180dkjngx99g1l65wr7b5784fslzbcv5r",
+        "rev": "1239ff7fb94bd647ea54d18e7c7da4b81e63f422",
+        "sha256": "1gfl9jasnds7frb9lkx4k0dkynkrlxriirqshwp79kbcjw3g6lnp",
         "type": "tarball",
-        "url": "https://github.com/NixOS/nixops/archive/ed2868fbc0b5924fcd4a60a8bd32a14fa196381b.tar.gz",
+        "url": "https://github.com/NixOS/nixops/archive/1239ff7fb94bd647ea54d18e7c7da4b81e63f422.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     },
     "nixpkgs": {