update link to empirehacking slack (trailofbits#14621)

Author: oldsj

docs/faq.md

@@ -17,7 +17,7 @@
 
 ## Has Algo been audited?
 
-No. This project is under active development. We're happy to [accept and fix issues](https://github.com/trailofbits/algo/issues) as they are identified. Use Algo at your own risk. If you find a security issue of any severity, please [contact us on Slack](https://empireslacking.herokuapp.com).
+No. This project is under active development. We're happy to [accept and fix issues](https://github.com/trailofbits/algo/issues) as they are identified. Use Algo at your own risk. If you find a security issue of any severity, please [contact us on Slack](https://slack.empirehacking.nyc).
 
 ## What's the current status of WireGuard?