* Use local copies of pebble certs as docker image contains outdated versions * Update the preferred chain used in Staging * Put test API keys in github secrets, add code to create/delete test domains to prevent misuse * Simplify dns_add_acmedns
and avoid to display the error twice on failure.
Needed for self-hosted servers.
ACME-DNS provide credentials for each domain. Each credential is allowed to update only its subdomain record.