[doc] feat: add SimpleVLA-RL link in readme (volcengine#3433)

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---------

Co-authored-by: ByteDance <[email protected]>
Co-authored-by: Chi Zhang <[email protected]>

Author: 3 people

README.md

@@ -236,6 +236,7 @@ verl is inspired by the design of Nemo-Aligner, Deepspeed-chat and OpenRLHF. The
 - [RL-PLUS](https://github.com/YihongDong/RL-PLUS): Countering Capability Boundary Collapse of LLMs in Reinforcement Learning with Hybrid-policy Optimization.
 - [rStar2-Agent](https://github.com/microsoft/rStar): Using reinforcement learning with multi-step tool-calling for math tasks, rStar2-Agent-14B reaches frontier-level math reasoning in just 510 RL training steps ![GitHub Repo stars](https://img.shields.io/github/stars/microsoft/rStar)
 - [Vision-SR1](https://github.com/zli12321/Vision-SR1): Self-Rewarding Vision-Language Model via Reasoning Decomposition ![GitHub Repo stars](https://img.shields.io/github/stars/zli12321/Vision-SR1)
+- [SimpleVLA-RL](https://github.com/PRIME-RL/SimpleVLA-RL): SimpleVLA-RL: A Simple yet Effective Vision-Language Action Model for Reinforcement Learning ![GitHub Repo stars](https://img.shields.io/github/stars/PRIME-RL/SimpleVLA-RL)
 
 and many more awesome work listed in [recipe](recipe/README.md).