nixos/display-managers: install sessionData.desktops

Fixes https://github.com/NixOS/nixpkgs/issues/100108

nixos/modules/services/x11/display-managers/default.nix

@@ -481,6 +481,13 @@ in
             )
             [dms wms]
           );
+
+    # Make xsessions and wayland sessions installed at
+    # /run/current-system/sw/share as some programs
+    # have behavior that depends on them being installed
+    environment.systemPackages = [
+      cfg.displayManager.sessionData.desktops
+    ];
   };
 
   imports = [