add logo for contrib repo

README.md

@@ -2,6 +2,13 @@
 title: 👋 Welcome
 sidebar_position: 1
 ---
+<p align="center">
+  <picture>
+    <source height="125" media="(prefers-color-scheme: dark)" srcset="https://raw.githubusercontent.com/gofiber/contrib/master/.github/logo-dark.svg">
+    <img height="125" alt="Fiber" src="https://raw.githubusercontent.com/gofiber/contrib/master/.github/logo.svg">
+  </picture>
+  <br>
+
 # Contrib
 
 [![Discord](https://img.shields.io/discord/704680098577514527?style=flat&label=%F0%9F%92%AC%20discord&color=00ACD7)](https://gofiber.io/discord)
@@ -11,6 +18,8 @@ sidebar_position: 1
 
 Repository for third party middlewares with dependencies.
 
+</p>
+
 ## 📑 Middleware Implementations
 
 * [Casbin](./casbin/README.md) <a href="https://github.com/gofiber/contrib/actions?query=workflow%3A%22Tests%22"> <img src="https://img.shields.io/github/actions/workflow/status/gofiber/contrib/test.yml?branch=main&label=%F0%9F%A7%AA%20&style=flat&color=75C46B" /> </a>