Refactor observer configuration in summer.js: format observer options for improved readability

Jellyfin.Plugin.Seasonals/Web/summer.js

@@ -34,8 +34,11 @@ function toggleSummer() {
 }
 
 const observer = new MutationObserver(toggleSummer);
-observer.observe(document.body, { childList: true, subtree: true, attributes: true });
-
+observer.observe(document.body, {
+  childList: true,
+  subtree: true,
+  attributes: true
+});
 function createBubble(container, isDust = false) {
     const bubble = document.createElement('div');