feat: fix README badges (#3)

README.md

diff --git a/README.md b/README.md
index 62d00fd..8e94736 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@
 [![Version](https://img.shields.io/pypi/v/casbin-graphql-authz.svg)](https://pypi.org/project/casbin-graphql-authz/)
 [![PyPI - Wheel](https://img.shields.io/pypi/wheel/casbin-graphql-authz.svg)](https://pypi.org/project/casbin-graphql-authz/)
 [![Pyversions](https://img.shields.io/pypi/pyversions/casbin-graphql-authz.svg)](https://pypi.org/project/casbin-graphql-authz/)
-[![Download](https://img.shields.io/pypi/dm/casbin-graphql-authz.svg)](https://pypi.org/project/casbin-graphql-authz/)
+[![Download](https://static.pepy.tech/badge/casbin-graphql-authz)](https://pypi.org/project/casbin-graphql-authz/)
 [![Discord](https://img.shields.io/discord/1022748306096537660?logo=discord&label=discord&color=5865F2)](https://discord.gg/S5UjpzGZjN)
 
 GraphQL-Authz is a Python port of [GraphQL-Authz](https://github.com/node-casbin/graphql-authz), the [Casbin](https://casbin.org/) authorization middleware implementation in [Node.js](https://nodejs.org/en/).