Add nix to goimapnotify user service path

Flake lock file updates:

• Updated input 'nixpkgs':
    'github:NixOS/nixpkgs/a72d7811be1162dd6804c4e36e5402d76fb6e921' (2022-06-21)
  → 'github:NixOS/nixpkgs/e1e08fe28bf0588a41cd556eac40b98d2793da99' (2022-06-22)

flake.lock

@@ -38,11 +38,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1655807518,
-        "narHash": "sha256-5YV29Ry/DpAJc/0Hc/+ISVBAjwHpJvAkeKkcUG5lWsc=",
+        "lastModified": 1655895887,
+        "narHash": "sha256-AbihSVmPKFcQmaVgzNSLQ8sLAaVTTELPSzZ+/gRVfyk=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "a72d7811be1162dd6804c4e36e5402d76fb6e921",
+        "rev": "e1e08fe28bf0588a41cd556eac40b98d2793da99",
         "type": "github"
       },
       "original": {

modules/periodic.nix

@@ -56,7 +56,8 @@ in {
   systemd.user.services.goimapnotify-ugent = {
     description = "Sync UGent mail using IMAP IDLE";
     wantedBy = [ "default.target" ];
-    path = [ goimapnotify pass-wayland isync-oauth2 notmuch python39 gnupg ];
+    path =
+      [ goimapnotify pass-wayland isync-oauth2 notmuch python39 gnupg nix ];
     script = ''
       ${pkgs.goimapnotify}/bin/goimapnotify -conf /home/coolneng/.config/goimapnotify/ugent.conf
     '';