Update Discord links from channels to forums (#440)

As our Discord community growths, we found it difficult to look for open and resolved issues in **#running-a-client** and **#running-a-server** channels, as well as navigate through interleaving conversations happening there. That's why we recreated these channels as Discord forums, where different discussions are separated into different posts.

README.md

@@ -37,7 +37,7 @@ print(tokenizer.decode(outputs[0]))  # A cat sat on a mat...
 
 🔏 **Privacy.** Your data will be processed by other people in the public swarm. Learn more about privacy [here](https://github.com/bigscience-workshop/petals/wiki/Security,-privacy,-and-AI-safety). For sensitive data, you can set up a [private swarm](https://github.com/bigscience-workshop/petals/wiki/Launch-your-own-swarm) among people you trust.
 
-💬 **Any questions?** Ping us in [our Discord](https://discord.gg/J29mCBNBvm)!
+💬 **Any questions?** Ping us in [our Discord](https://discord.gg/KdThf2bWVU)!
 
 ### Connect your GPU and increase Petals capacity
 
@@ -68,7 +68,7 @@ These commands will host a part of [Stable Beluga 2](https://huggingface.co/stab
 python -m petals.cli.run_server meta-llama/Llama-2-70b-chat-hf --token YOUR_TOKEN_HERE
 ```
 
-💬 **FAQ.** Check out our [Wiki](https://github.com/bigscience-workshop/petals/wiki/FAQ:-Frequently-asked-questions#running-a-server) to learn how to use multple GPUs, restart the server on reboot, etc. If you have any issues, ping us in [our Discord](https://discord.gg/D9MwApKgWa)!
+💬 **FAQ.** Check out our [Wiki](https://github.com/bigscience-workshop/petals/wiki/FAQ:-Frequently-asked-questions#running-a-server) to learn how to use multple GPUs, restart the server on reboot, etc. If you have any issues, ping us in [our Discord](https://discord.gg/X7DgtxgMhc)!
 
 🔒 **Security.** Hosting a server does not allow others to run custom code on your computer. Learn more [here](https://github.com/bigscience-workshop/petals/wiki/Security,-privacy,-and-AI-safety).