Point Jenkins slaves to the migrated secrets repo (sysadmin#17729)

manifests/jenkins/slave/iso_tester.pp

@@ -9,7 +9,7 @@ class tails::jenkins::slave::iso_tester (
   $temp_dir_backing_device               = undef,
   String $temp_dir_fs_type               = 'ext4',
   String $temp_dir_mount_options         = 'relatime,acl',
-  String $test_suite_shared_secrets_repo = 'tails@git.tails.boum.org:test-suite-shared-secrets',
+  String $test_suite_shared_secrets_repo = 'git@gitlab-ssh.tails.boum.org:tails/test-suite-shared-secrets.git',
   Boolean $manage_email_server           = true,
 ) {