fix: environment variables missed in nushell

fix: https://github.com/ryan4yin/nix-config/issues/26

home/darwin/default.nix

@@ -5,7 +5,6 @@
     ./proxychains
 
     ./core.nix
-    ./nushell.nix
     ./rime-squirrel.nix
   ];
 

home/darwin/nushell.nix

@@ -1,18 +0,0 @@
-{config, ...}: {
-  # nix-darwin do not set PATH for nushell! so we need to do it manually
-  # this is a workaround to add nix's PATH to nushell
-  programs.nushell.extraConfig = ''
-    $env.PATH = ([
-      "${config.home.homeDirectory}/bin"
-      "${config.home.homeDirectory}/.local/bin"
-      "${config.home.homeDirectory}/go/bin"
-      "/usr/local/bin"
-      "${config.home.homeDirectory}/.nix-profile/bin"
-      "/etc/profiles/per-user/${config.home.username}/bin"
-      "/run/current-system/sw/bin"
-      "/nix/var/nix/profiles/default/bin"
-
-      ($env.PATH | split row (char esep))
-    ] | flatten)
-  '';
-}