mkNugetSource: Remove meta.licenses attribute

- It's useless. The correct attribute name would be `license` and not
  `licenses`. Meaning setting this never did anything useful.
- It used IFD in its implementation, meaning to know what the licenses
  of a nuget source are, you first had to build that nuget source. This
  defeats the point of having license checks in the first place.
- IFD is not allowed by the nixpkgs CI and build farm anyway.

pkgs/build-support/dotnet/make-nuget-source/default.nix

@@ -5,8 +5,7 @@
 , deps ? []
 }:
 
-let
+stdenvNoCC.mkDerivation {
-  nuget-source = stdenvNoCC.mkDerivation {
   inherit name;
 
   nativeBuildInputs = [ python3 ];
@@ -25,14 +24,4 @@ let
   '';
 
   meta.description = description;
-  } // { # We need data from `$out` for `meta`, so we have to use overrides as to not hit infinite recursion.
+}
-    meta = nuget-source.meta // {
-      licenses = let
-        # TODO: avoid IFD
-        depLicenses = lib.splitString "\n" (builtins.readFile "${nuget-source}/share/licenses");
-      in lib.flatten (lib.forEach depLicenses (spdx:
-        lib.optionals (spdx != "") (lib.getLicenseFromSpdxId spdx)
-      ));
-    };
-  };
-in nuget-source