Remove bluemail.

It's screwing up my email really badly. Mostly by putting mail in
impossible-to-reach folders from other email clients.

nalai/etc/nixos/configuration.nix

@@ -120,13 +120,12 @@
   programs.neovim.defaultEditor = true;
 
   nixpkgs.config.allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [
-    "bluemail" "spotify"
+    "spotify"
   ];
 
   # List packages installed in system profile. To search, run:
   # $ nix search wget
   environment.systemPackages = with pkgs; [
-    bluemail
     cargo
     chezmoi
     cups-filters