docs: use ESM code in examples (#9427)

* docs(Partials): use import statement

* docs: update readme to ESM

---------

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

packages/discord.js/README.md

@@ -57,7 +57,7 @@ pnpm add discord.js
 Register a slash command against the Discord API:
 
 ```js
-const { REST, Routes } = require('discord.js');
+import { REST, Routes } from 'discord.js';
 
 const commands = [
   {
@@ -68,23 +68,21 @@ const commands = [
 
 const rest = new REST({ version: '10' }).setToken(TOKEN);
 
-(async () => {
-  try {
-    console.log('Started refreshing application (/) commands.');
+try {
+  console.log('Started refreshing application (/) commands.');
 
-    await rest.put(Routes.applicationCommands(CLIENT_ID), { body: commands });
+  await rest.put(Routes.applicationCommands(CLIENT_ID), { body: commands });
 
-    console.log('Successfully reloaded application (/) commands.');
-  } catch (error) {
-    console.error(error);
-  }
-})();
+  console.log('Successfully reloaded application (/) commands.');
+} catch (error) {
+  console.error(error);
+}
 ```
 
 Afterwards we can create a quite simple example bot:
 
 ```js
-const { Client, GatewayIntentBits } = require('discord.js');
+import { Client, GatewayIntentBits } from 'discord.js';
 const client = new Client({ intents: [GatewayIntentBits.Guilds] });
 
 client.on('ready', () => {

packages/discord.js/src/util/Partials.js

@@ -5,7 +5,7 @@ const { createEnum } = require('./Enums');
 /**
  * The enumeration for partials.
  * ```js
- * const { Client, Partials } = require('discord.js');
+ * import { Client, Partials } from 'discord.js';
  *
  * const client = new Client({
  *   intents: [