config: rotate key used to sign external signature requests

config/debian-security/dak.conf

@@ -186,5 +186,5 @@ External-Signature-Requests {
     "stable";
   };
   Export "/srv/security-master.debian.org/build-queues/project/external-signatures/requests.json";
-  ExportSigningKeys { "AD7B928FBB67C45A4A484560A275AE756013B497"; };
+  ExportSigningKeys { "AA6C6D7FECC2E7EED05CDB4EAAC8C6B0AF06C355"; };
 };

config/debian/dak.conf

@@ -314,5 +314,5 @@ External-Signature-Requests {
     "stretch-backports";
   };
   Export "/srv/ftp-master.debian.org/public/incoming.debian.org/web/debian-buildd/project/external-signatures/requests.json";
-  ExportSigningKeys { "69E6775AC793814879D7406D761F1FE865C742EC"; };
+  ExportSigningKeys { "8B46F1B8C09D0EC19E9C458C6DF948E711DF2F06"; };
 };