[Docs] Reorder README badges (#1128)

README.md

@@ -1,15 +1,16 @@
-[![ci](https://github.com/sotetsuk/pgx/actions/workflows/ci.yml/badge.svg)](https://github.com/sotetsuk/pgx/actions/workflows/ci.yml)
-[![Python](https://img.shields.io/badge/python-3.8%20%7C%203.9%20%7C%203.10%20%7C%203.11%20%7C%203.12-blue)](https://www.python.org/)
-[![PyPI version](https://badge.fury.io/py/pgx.svg)](https://pypi.org/project/pgx/)
-[![License](https://img.shields.io/badge/license-Apache%202.0-green.svg)](https://opensource.org/licenses/Apache-2.0)
-[![codecov](https://codecov.io/github/sotetsuk/pgx/graph/badge.svg?token=JNJIQ83JYG)](https://codecov.io/github/sotetsuk/pgx)
-[![arXiv](https://img.shields.io/badge/arXiv-2303.17503-b31b1b.svg)](https://arxiv.org/abs/2303.17503)
-
-
 <div align="center">
 <img src="https://raw.githubusercontent.com/sotetsuk/pgx/main/docs/assets/logo.svg" width="40%">
 </div>
 
+<p align="center">
+<a href="https://www.python.org/"><img alt="python" src="https://img.shields.io/badge/python-3.8%20%7C%203.9%20%7C%203.10%20%7C%203.11%20%7C%203.12-blue"></a>
+<a href="https://pypi.org/project/pgx/"><img alt="pypi" src="https://badge.fury.io/py/pgx.svg"></a>
+<a href="https://opensource.org/licenses/Apache-2.0"><img alt="license" src="https://img.shields.io/badge/license-Apache%202.0-green.svg"></a>
+<a href="https://github.com/sotetsuk/pgx/actions/workflows/ci.yml"><img alt="ci" src="https://github.com/sotetsuk/pgx/actions/workflows/ci.yml/badge.svg"></a>
+<a href="https://codecov.io/github/sotetsuk/pgx"><img alt="codecov" src="https://codecov.io/github/sotetsuk/pgx/graph/badge.svg?token=JNJIQ83JYG"></a>
+<a href="https://arxiv.org/abs/2303.17503"><img alt="arxiv" src="https://img.shields.io/badge/arXiv-2303.17503-b31b1b.svg"></a>
+</p>
+
 A collection of GPU/TPU-accelerated parallel game simulators for reinforcement learning (RL)
 
 <div align="center">