[misc] feat: update instruction for running dapo on qwen2.5 7b math and add reference wandb (#2094)

### Checklist Before Starting

- [x] Searched for similar PR(s).
- [x] Checked PR Title format
  - In format of: [modules] type: Title
- modules are in `fsdp, megatron, sglang, vllm, rollout, trainer, ci,
training_utils, recipe, hardware, deployment, ray, worker,
single_controller, misc, perf, model, algo, env, tool, ckpt, doc, data`
  - type is in `feat, fix, refactor, chore, test`
- can involve multiple modules, seperated by `,` or space, like
`[megatron, fsdp, doc] feat: xxx`

### What does this PR do?

- As title

### Test

> For changes that can not be tested by CI (e.g., algorithm
implementation, new model support), validate by experiment(s) and show
results like training curve plots, evaluatuion results, etc.

### High-Level Design

> Demonstrate the high-level design if this PR is complex.

### Specific Changes

> List the specific changes.

### API

> Demonstrate how the API changes if any.

### Usage Example

> Provide usage example(s) for easier usage.

```python
# Add code snippet or script demonstrating how to use this 
```

### Checklist Before Submitting

- [ ] Read the [Contribute
Guide](https://github.com/volcengine/verl?tab=readme-ov-file#contribution-guide).
- [ ] Apply [pre-commit
checks](https://github.com/volcengine/verl?tab=readme-ov-file#code-linting-and-formatting).
- [ ] Add `[BREAKING]` to the PR title `description` if it breaks any
API.
- [ ] Update the documentation about your changes in the
[docs](https://github.com/volcengine/verl/tree/main/docs).
- [ ] New CI unit test(s) are added to cover the code path.
- [ ] Rely on existing unit tests on CI that covers the code path.

recipe/dapo/test_dapo_7b_math.sh

@@ -34,6 +34,7 @@ NNODES=${NNODES:-8}
 NGPUS_PER_NODE=${NGPUS_PER_NODE:-8}
 # Paths
 RAY_DATA_HOME=${RAY_DATA_HOME:-"${HOME}/verl"}
+# very important! please modify the max_position_embeddings in config.json to 32768 after downloading from huggingface
 MODEL_PATH=${MODEL_PATH:-"${RAY_DATA_HOME}/models/Qwen2.5-Math-7B"}
 CKPTS_DIR=${CKPTS_DIR:-"${RAY_DATA_HOME}/ckpts/${project_name}/${exp_name}"}
 TRAIN_FILE=${TRAIN_FILE:-"${RAY_DATA_HOME}/data/dapo-math-17k.parquet"}
@@ -54,7 +55,7 @@ offload=True
 gen_tp=4
 fsdp_size=32
 
-# remember to set VLLM_ALLOW_LONG_MAX_MODEL_LEN=1 for this model
+# reference run wandb: https://wandb.ai/verl-org/DAPO%20Reproduction%20on%20verl/runs/ow47vvon?nw=nwusertongyuxuan361
 
 python3 -m verl.trainer.main_ppo \
     data.train_files="${TRAIN_FILE}" \