cups service: fix missing upstream systemd units caused by output splitting

Need to pass `cups.out` to `systemd.packages`, lest we end up with an invalid
generated unit containing only directives set in the service module.

This patch gives us a valid cups.service unit but, vexingly, does not fix the
test failure at NixOS/nixpkgs#14748

1 files changed, 1 insertions, 1 deletions

diff --git a/nixos/modules/services/printing/cupsd.nix b/nixos/modules/services/printing/cupsd.nix
index 29166be2399b..e4c96c24e64b 100644
--- a/nixos/modules/services/printing/cupsd.nix
+++ b/nixos/modules/services/printing/cupsd.nix
@@ -277,7 +277,7 @@ in
     # gets loaded, and then cups cannot access the printers.
     boot.blacklistedKernelModules = [ "usblp" ];
 
-    systemd.packages = [ cups ];
+    systemd.packages = [ cups.out ];
 
     systemd.services.cups =
       { wantedBy = [ "multi-user.target" ];