Add hackerone link to SECURITY.md. (jitsi#1164)

SECURITY.md

@@ -1,9 +1,9 @@
 # Security
 
-## Reporting security issuess
+## Reporting security issues
 
 We take security very seriously and develop all Jitsi projects to be secure and safe.
 
-If you find (or simply suspect) a security issue in any of the Jitsi projects, please send us an email to security@jitsi.org.
+If you find (or simply suspect) a security issue in any of the Jitsi projects, please report it to us via [HackerOne](https://hackerone.com/8x8-bounty) or send us an email to security@jitsi.org.
 
 **We encourage responsible disclosure for the sake of our users, so please reach out before posting in a public space.**