sketchybar: inherit meta in finalPackage (#7276)

Since we're creating a new derivation, we drop the original package
attributes. Add our own meta.mainProgram to resolve those warnings.

Signed-off-by: Austin Horstman <khaneliman12@gmail.com>

modules/programs/sketchybar.nix

@@ -247,6 +247,7 @@ in
           postBuild = ''
             wrapProgram $out/bin/sketchybar ${lib.escapeShellArgs makeWrapperArgs}
           '';
+          inherit (cfg.package) meta;
         }
       else
         cfg.package;