emacs: let hydra not build epkgs to speed up bumping default Emacs

Emacs 30 fixes two CVEs.  With this patch, bumping default Emacs
version can go to master instead of staging.

Author: jian-lin

pkgs/top-level/aliases.nix

@@ -419,6 +419,7 @@ mapAliases {
   emacsMacport = emacs-macport; # Added 2023-08-10
   emacsNativeComp = emacs28NativeComp; # Added 2022-06-08
   emacsWithPackages = throw "'emacsWithPackages' has been renamed to/replaced by 'emacs.pkgs.withPackages'"; # Converted to throw 2024-10-17
+  emacsPackages = emacs.pkgs; # Added 2025-03-02
 
   EmptyEpsilon = empty-epsilon; # Added 2024-07-14
   enyo-doom = enyo-launcher; # Added 2022-09-09

pkgs/top-level/all-packages.nix

@@ -13194,10 +13194,6 @@ with pkgs;
     pkgs' = pkgs;  # default pkgs used for bootstrapping the emacs package set
   };
 
-  # This alias should live in aliases.nix but that would cause Hydra not to evaluate/build the packages.
-  # If you turn this into "real" alias again, please add it to pkgs/top-level/packages-config.nix again too
-  emacsPackages = emacs.pkgs // { __recurseIntoDerivationForReleaseJobs = true; };
-
   epick = callPackage ../applications/graphics/epick {
     inherit (darwin.apple_sdk.frameworks) AppKit;
   };

pkgs/top-level/packages-config.nix

@@ -36,6 +36,10 @@
         compiler = recurseIntoAttrs super.haskell.compiler;
       };
 
+      # emacsPackages is an alias for emacs.pkgs
+      # Re-introduce emacsPackages here so that emacs.pkgs can be searched.
+      emacsPackages = emacs.pkgs;
+
       # minimal-bootstrap packages aren't used for anything but bootstrapping our
       # stdenv. They should not be used for any other purpose and therefore not
       # show up in search results or repository tracking services that consume our