Add HaveIBeenSold to Credentials section

README.md

@@ -338,6 +338,7 @@ A curated list of awesome search engines useful during Penetration testing, Vuln
 - [ntlm.pw](https://ntlm.pw/) - Instantly look up NTLM hashes and resolve them to plaintext passwords using our database with 8B+ entries
 - [Hudson Rock](https://www.hudsonrock.com/threat-intelligence-cybercrime-tools) - Use Hudson Rock’s free cybercrime intelligence tools to learn how compromised credentials are impacting your business
 - [hackedlist.io](https://hackedlist.io/) - Enter your domain to find credentials compromised by info-stealer malware
+- [HaveIBeenSold](https://haveibeensold.app/) - Lets you find out whether or not your email has been sold to third parties
 
 ### Leaks