Remove security section from README, add SECURITY.md

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Author: spawnia

README.md

@@ -62,10 +62,6 @@ When upgrading between major versions of Lighthouse, consider [`UPGRADE.md`](UPG
 
 We welcome contributions of any kind, see how in [`CONTRIBUTING.md`](CONTRIBUTING.md).
 
-## Security Vulnerabilities
-
-If you discover a security vulnerability within Lighthouse, email Benedikt Franke at [benedikt@franke.tech](mailto:benedikt@franke.tech).
-
 ## Sponsors
 
 Lighthouse is supported by [its awesome sponsors](https://lighthouse-php.com/sponsors).

SECURITY.md

@@ -0,0 +1,7 @@
+# Security Policy
+
+## Reporting a Vulnerability
+
+Please report security vulnerabilities through [GitHub's private vulnerability reporting](https://github.com/nuwave/lighthouse/security/advisories/new).
+
+Do not open public issues for security vulnerabilities.