2025-06-openapi-generator: fixed link

Author: JohannesHoppe

blog/2025-06-openapi-generator/README.md

@@ -99,7 +99,7 @@ You can also use this mechanism to test new versions or roll back safely.
 
 ## Generating Your First Angular API Client
 
-Before we take a look at the code, take a moment to explore [https://api6.angular-buch.com/](api6.angular-buch.com).
+Before we take a look at the code, take a moment to explore [api6.angular-buch.com](https://api6.angular-buch.com/).
 
 This public REST API is part of the **BookMonkey 6** demo application, the updated companion project for the upcoming **5th edition** of our German Angular book.