update vulnerability report link (zalando#2036)

Signed-off-by: Sandor Szücs <[email protected]>

Author: szuecs

SECURITY.md

@@ -3,7 +3,7 @@ We are trying to deal with it responsibly and provide patches as quickly as poss
 
 We host our bug bounty program on HackerOne, it is currently private, therefore if you would like to report a vulnerability and get rewarded for it, please ask to join our program by filling this form:
 
-https://corporate.zalando.com/en/services-and-contact#security-form
+https://zeng.page.link/open-source-report-vulnerability
 
 You can also send you report via this form if your do not want to join our bug bounty program and just want to report a vulnerability or security issue.