TLS example certs have expired

[kpvdr]

The SSL certs checked in with the examples have expired. Running these examples fail with CERT_HAS_EXPIRED. In addition, there appears to be an unhandled exception related to the failure.

stderr[sasl/sasl_anonymous_server.js]: node:events:491
      throw er; // Unhandled 'error' event
      ^

It is a simple matter to generate the certs if an openssl package is present (as described in the README for the tls example), so perhaps a better approach would be to use a script to generate the certs prior to running the examples rather than checking in the certs themselves.