config: load cacerts from SSL_CERT_FILE before using it
This fixes a build error on systems like NixOS that don't have a fixed location for cacerts but instead point applications to the system certs with the SSL_CERT_FILE env variable.
This fixes a build error on systems like NixOS that don't have a fixed location for cacerts but instead point applications to the system certs with the SSL_CERT_FILE env variable.