Update README.md

Author: just1and0

README.md

@@ -13,8 +13,8 @@ This package lets you accept payments with Paystack in a snap! Just install, add
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- <img width="306" alt="Screenshot of library in action" src="https://user-images.githubusercontent.com/41248079/126550307-5f12c6d8-81af-4f26-951b-5d6514304022.png">
+<div align="center">
+  <img width="306" alt="Screenshot of library in action" src="https://user-images.githubusercontent.com/41248079/126550307-5f12c6d8-81af-4f26-951b-5d6514304022.png">
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