Move waybar style to waybar folder

wm/waybar.nix

@@ -4,7 +4,7 @@
   programs.waybar = {
     enable = true;
 
-    style = builtins.readFile ./waybar-style.css;
+    style = builtins.readFile ./waybar/waybar-style.css;
 
     settings.mainBar = {
       layer = "top";