treewide: remove redundant stylix.image escaping and string coercion

Remove redundant shell escaping and string coercion as stylix.image is
guaranteed to be a stringified store path with a valid string context
and no special characters.

Fixes: 3499e3ec70 ("treewide: properly quote stylix.image when used as a shell argument")
(cherry picked from commit 61c9f4dd14)

modules/hyprlock/hm.nix

@@ -11,9 +11,7 @@ mkTarget {
     (
       { cfg, image }:
       {
-        programs.hyprlock.settings.background.path = lib.mkIf cfg.useWallpaper "${
-          image
-        }";
+        programs.hyprlock.settings.background.path = lib.mkIf cfg.useWallpaper image;
       }
     )
     (

modules/hyprpaper/hm.nix

@@ -4,7 +4,7 @@ mkTarget {
     { image }:
     {
       services.hyprpaper.settings = {
-        preload = [ "${image}" ];
+        preload = [ image ];
         wallpaper = [ ",${image}" ];
       };
     };