chore: updated discord invite link (#6374)

# What does this PR do?
Old discord invite link is invalid

This invite link will be invalid in another 30 days. (3rd Sept.)

Signed-off-by: dominikkawka <dominikkawka2002@gmail.com>

Author: dominikkawka

README.md

@@ -12,7 +12,7 @@
   <a href="https://deepwiki.com/ogx-ai/ogx"><img src="https://deepwiki.com/badge.svg" alt="Ask DeepWiki"></a>
 </p>
 
-[**Quick Start**](https://ogx-ai.github.io/docs/getting_started/quickstart) | [**Documentation**](https://ogx-ai.github.io/docs) | [**OpenAI API Compatibility**](https://ogx-ai.github.io/docs/api-openai) | [**Discord**](https://discord.gg/bUYRqEvK6)
+[**Quick Start**](https://ogx-ai.github.io/docs/getting_started/quickstart) | [**Documentation**](https://ogx-ai.github.io/docs) | [**OpenAI API Compatibility**](https://ogx-ai.github.io/docs/api-openai) | [**Discord**](https://discord.gg/E8M7xraH8)
 
 > [!IMPORTANT]
 > **Llama Stack is now OGX.** The name changed, and so did the mission — model-agnostic, multi-SDK, production-grade. [Read the full announcement →](https://ogx-ai.github.io/blog/from-llama-stack-to-ogx)