feat: Setting background synchronization (#3331)

* Changing the background synchronization setting

* add  example

* return function

* style: add clarification note

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Co-authored-by: alechkos <93551621+alechkos@users.noreply.github.com>
Co-authored-by: Shir Serlui <70711723+shirser121@users.noreply.github.com>

example.js

@@ -470,6 +470,10 @@ client.on('message', async msg => {
         console.log(statuses);
         const chat = await statuses[0]?.getChat(); // Get user chat of a first status
         console.log(chat);
+    } else if (msg.body === '!changeSync') {
+        // NOTE: this action will take effect after you restart the client.
+        const backgroundSync = await client.setBackgroundSync(true);
+        console.log(backgroundSync);
     }
 });