### What this PR does / why we need it?
Since the mooncake has the newer
[release](https://github.com/kvcache-ai/Mooncake/releases/tag/v0.3.8.post1),
we pin the tag to latest release
### Does this PR introduce _any_ user-facing change?
### How was this patch tested?
- vLLM version: v0.13.0
- vLLM main:
d68209402d
Signed-off-by: wangli <wangli858794774@gmail.com>