fix: fix typo on day50 in 2023

Author: Eeap

2023/day50.md

@@ -42,4 +42,4 @@ Once you have access to your free tier account, there are a few additional steps
 [Create your free AWS account](https://youtu.be/uZT8dA3G-S4)
 
 [Generate credentials, budget, and billing alarms via CLI](https://youtu.be/OdUnNuKylHg)
-See you in [Day 52](day52.md).
+See you in [Day 51](day51.md).