update readme to correct link

Author: Todd Burner

README.md

@@ -1,7 +1,7 @@
 Android Security Samples Repository
 ===================================
 
-## [Android Developer Verification Onboarding](https://github.com/android/security-samples/tree/main/AndroidDeveloperVerificationOnboarding)
+## [Android Developer Verification APK Signing Example](https://github.com/android/security-samples/tree/main/AndroidDeveloperVerificationAPKSigningExample)
 
 This project shows you exactly which file to create (adi-registration.properties) and provides the necessary folder structure to guide you. Use this template to check your placement of the file and ensure the correct insertion of your unique developer 'snippet' for successful verification.