docs(contribute): fix donate button rendering

Author: Sahilshrma31

src/content/contribute/index.mdx

@@ -13,7 +13,7 @@ contributors:
 
 The people who contribute to webpack do so for the love of open source, our users and ecosystem, and most importantly, pushing the web forward together. Because of our [Open Collective](https://opencollective.com/webpack) model for funding and transparency, we are able to funnel support and funds through contributors, dependent projects, and the contributor and core teams. To make a donation, click the button below...
 
-<div align="center">
+<div className="flex justify-center">
 
 <a
   href="https://opencollective.com/webpack/donate"