docs(README): fix gpumode discord badge (#835)

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Co-authored-by: Vaibhav Jindal <[email protected]>

Author: Tcc0403

README.md

@@ -32,7 +32,7 @@
         </td>
         <td style="padding: 10px;">
             <a href="https://discord.gg/gpumode">
-                <img src="https://dcbadge.vercel.app/api/server/gpumode?style=flat" alt="Join Our Discord">
+                <img src="https://dcbadge.limes.pink/api/server/gpumode?style=flat" alt="Join Our Discord">
             </a>
         </td>
     </tr>