Revert "release: disallow aliases"

This reverts commit 25c42e7736.

This commit is still causing evaluation errors (despite passing
OfBorg!)

Here is the current error:

error: undefined variable 'Log4Perl' at
/nix/store/n0gwyv3mcvm3hc9jrmkxjhmsrdjqzcqb-source/maintainers/scripts/nix-generate-from-cpan.nix:7:71

More investigation is needed

/cc @volth

pkgs/top-level/release.nix

@@ -16,7 +16,7 @@
   # Strip most of attributes when evaluating to spare memory usage
 ,  scrubJobs ? true
   # Attributes passed to nixpkgs. Don't build packages marked as unfree.
-,  nixpkgsArgs ? { config = { allowUnfree = false; inHydra = true; allowAliases = false; }; }
+,  nixpkgsArgs ? { config = { allowUnfree = false; inHydra = true; }; }
 }:
 
 with import ./release-lib.nix { inherit supportedSystems scrubJobs nixpkgsArgs; };