### What this PR does / why we need it?
Fix word spelling in DOC.
### Does this PR introduce _any_ user-facing change?
No.
### How was this patch tested?
No.
Signed-off-by: paulyu12 <507435917@qq.com>
### What this PR does / why we need it?
Add LoRA user guide to DOC. The content refers to [LoRA
Adapters](https://docs.vllm.ai/en/latest/features/lora.html).
### Does this PR introduce _any_ user-facing change?
No
### How was this patch tested?
No
---------
Signed-off-by: paulyu12 <507435917@qq.com>