Update README.md (#40)

Author: Abdul-0x4A

README.md

@@ -53,7 +53,7 @@ Install LitAI via pip ([more options](https://lightning.ai/docs/litai/home/insta
 ```bash
 pip install litai
 ```
-Get your API key [here](https://lightning.ai/) and chat with any AI model in 3 lines:
+Get your API key [here](https://lightning.ai/sign-up?okbhrt=x334uv8t7v) and chat with any AI model in 3 lines:
 
 ```python
 from litai import LLM