remove dead links

Author: rieckpil

README.md

@@ -4,12 +4,6 @@
 
 If you find an issue or bug within the provided code examples, feel free to open an [issue](https://github.com/rieckpil/blog-tutorials/issues), and we'll take a look.
 
-## Cheat Sheets
-
-* [Testing Java Applications Cheat Sheet](https://rieckpil.de/testing-java-applications-cheat-sheet/)
-* [Java EE & Jakarta EE Application Server Cheat Sheet](https://rieckpil.de/cheatsheet-java-jakarta-ee-application-servers/) ([Sources](https://github.com/rieckpil/blog-tutorials/tree/master/application-server-cheatsheet))
-* [Spring Web MVC Cheat Sheet](https://rieckpil.de/spring-web-mvc-cheat-sheet/) ([Sources](https://github.com/rieckpil/blog-tutorials/tree/master/))
-
 ## Articles about Testing
 
 * [Generating Java Test Data With Instancio](https://rieckpil.de/generating-java-test-data-with-instancio/) ([Sources](https://github.com/rieckpil/blog-tutorials/tree/master/generating-test-data-with-instancio))