Create a PDL runtime optimization benchmark

[esnible]

Is your feature request related to a problem? Please describe.
Create a PDL runtime optimization benchmark

Describe the solution you'd like
TBD

[esnible]

@mandel recommends https://github.com/sgl-project/sglang/tree/main/benchmark

[esnible]

@vazirim is considering https://arxiv.org/abs/2312.07104 , specifically "Tree-of-thought" GSM-8K.

[vazirim]

We could start with zero-shot GSM-8k