update docs/api-inference/rate-limits.md

**Doc request**
Please update "docs/api-inference/rate-limits.md". I noticed that the rate limits are changed to daily basis instead of an hourly basis

**Additional context**
I have never used github so have mercy please. I also don't know if this is the right spot

**Link**
https://github.com/huggingface/hub-docs/blob/main/docs/api-inference/rate-limits.md