fix: broken link

Author: lidel

src/ipips/ipip-0386.md

@@ -68,7 +68,7 @@ root.
 This change subsequently fixes the resolution of native URLs in browsers using
 the companion extension and browsers like Brave.
 
-A paragraph is added to the [`SUBDOMAIN_GATEWAY.md`](../SUBDOMAIN_GATEWAY.md)
+A paragraph is added to the :cite[subdomain-gateway]
 spec that describes the preservation of path segments and query parameters
 during the interop redirect. Furthermore, it specifies that gateway
 implementations should redirect to subdomain URLs if a resource is initially