docs(Welcome): change discord badge to shields.io for consistency (#4633)

Author: advaith1

README.md

@@ -5,7 +5,7 @@
   </p>
   <br />
   <p>
-    <a href="https://discord.gg/bRCvFy9"><img src="https://discord.com/api/guilds/222078108977594368/embed.png" alt="Discord server" /></a>
+    <a href="https://discord.gg/bRCvFy9"><img src="https://img.shields.io/discord/222078108977594368?color=7289da&logo=discord&logoColor=white" alt="Discord server" /></a>
     <a href="https://www.npmjs.com/package/discord.js"><img src="https://img.shields.io/npm/v/discord.js.svg?maxAge=3600" alt="NPM version" /></a>
     <a href="https://www.npmjs.com/package/discord.js"><img src="https://img.shields.io/npm/dt/discord.js.svg?maxAge=3600" alt="NPM downloads" /></a>
     <a href="https://github.com/discordjs/discord.js/actions"><img src="https://github.com/discordjs/discord.js/workflows/Testing/badge.svg" alt="Build status" /></a>

docs/general/welcome.md

@@ -5,7 +5,7 @@
   </p>
   <br />
   <p>
-    <a href="https://discord.gg/bRCvFy9"><img src="https://discord.com/api/guilds/222078108977594368/embed.png" alt="Discord server" /></a>
+    <a href="https://discord.gg/bRCvFy9"><img src="https://img.shields.io/discord/222078108977594368?color=7289da&logo=discord&logoColor=white" alt="Discord server" /></a>
     <a href="https://www.npmjs.com/package/discord.js"><img src="https://img.shields.io/npm/v/discord.js.svg?maxAge=3600" alt="NPM version" /></a>
     <a href="https://www.npmjs.com/package/discord.js"><img src="https://img.shields.io/npm/dt/discord.js.svg?maxAge=3600" alt="NPM downloads" /></a>
     <a href="https://travis-ci.org/discordjs/discord.js"><img src="https://travis-ci.org/discordjs/discord.js.svg" alt="Build status" /></a>