How to automatically add TLS certificates to Oracle wallets?

When accessing external webservices via HTTPS via the Oracle database you need to add the corresponding certificate to a database wallet to prevent a certificate validation error. When one creates an account at apex.oracle.com, one is able to access any external HTTPS webservice without the need to add certificates. So, Oracle seems to have some automated process in place to add the certificates when they are needed. My question is: How would you go about to do that? Or am I missing some "auto-add" feature?