[1/2/N] Enable pymarkdown and python __init__ for lint system (#2011)

### What this PR does / why we need it?
1. Enable pymarkdown check
2. Enable python `__init__.py` check for vllm and vllm-ascend
3. Make clean code

### How was this patch tested?


- vLLM version: v0.9.2
- vLLM main:
29c6fbe58c

---------

Signed-off-by: wangli <wangli858794774@gmail.com>

docs/source/developer_guide/evaluation/using_evalscope.md

@@ -65,6 +65,7 @@ pip install gradio plotly evalscope
 ## 3. Run gsm8k accuracy test using EvalScope
 
 You can `evalscope eval` run gsm8k accuracy test:
+
 ```
 evalscope eval \
  --model Qwen/Qwen2.5-7B-Instruct \
@@ -98,6 +99,7 @@ pip install evalscope[perf] -U
 ### Basic usage
 
 You can use `evalscope perf` run perf test:
+
 ```
 evalscope perf \
     --url "http://localhost:8000/v1/chat/completions" \
@@ -111,7 +113,7 @@ evalscope perf \
 
 ### Output results
 
-After 1-2 mins, the output is as shown below: 
+After 1-2 mins, the output is as shown below:
 
 ```shell
 Benchmarking summary: