nickel: update GitHub owner name

pkgs/by-name/ni/nickel/package.nix

@@ -17,7 +17,7 @@ rustPlatform.buildRustPackage (finalAttrs: {
   version = "1.16.0";
 
   src = fetchFromGitHub {
-    owner = "tweag";
+    owner = "nickel-lang";
     repo = "nickel";
     tag = finalAttrs.version;
     hash = "sha256-G+ik4tMr+WsDpiEFYv80ruBR/SpeEg9agUWqgXrq7UI=";
@@ -93,7 +93,7 @@ rustPlatform.buildRustPackage (finalAttrs: {
       that are then fed to another system. It is designed to have a simple,
       well-understood core: it is in essence JSON with functions.
     '';
-    changelog = "https://github.com/tweag/nickel/blob/${finalAttrs.version}/RELEASES.md";
+    changelog = "https://github.com/nickel-lang/nickel/blob/${finalAttrs.version}/RELEASES.md";
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [
       felschr