Add link to security.txt

SECURITY.md

@@ -8,6 +8,6 @@ The supported version is always the latest major release available in our reposi
 
 ## Reporting a Vulnerability
 
-If you find a vulnerability in our software, please email the Timescale Security Team at [email protected].
+If you find a vulnerability in our software, please email the [Timescale Security Team](https://www.timescale.com/.well_known/security.txt) at [email protected].
 
 Please note that the e-mail address should only be used for reporting undisclosed security vulnerabilities in Timescale products and services.  Regular bug reports should be submitted as GitHub issues, while other _questions_ around security, compliance, or functionality can be made either through our support (for customers) or community channels (e.g., [Timescale Slack](https://slack.timescale.com/), [Forums](https://www.timescale.com/forums), etc.)