Warn when API cannot be started on HTTPs

[josecelano]

// Run the API server
let join_handle = tokio::spawn(async move {
    if !ssl_enabled {
        info!("Starting Torrust APIs server on: http://{}", bind_addr);

        let handle = server::start(bind_addr, &tracker);

        tx.send(ApiServerJobStarted()).expect("the API server should not be dropped");

        if let Ok(()) = handle.await {
            info!("Torrust APIs server on http://{} stopped", bind_addr);
        }
    } else if ssl_enabled && ssl_cert_path.is_some() && ssl_key_path.is_some() {
        info!("Starting Torrust APIs server on: https://{}", bind_addr);

        let ssl_config = RustlsConfig::from_pem_file(ssl_cert_path.unwrap(), ssl_key_path.unwrap())
            .await
            .unwrap();

        let handle = server::start_tls(bind_addr, ssl_config, &tracker);

        tx.send(ApiServerJobStarted()).expect("the API server should not be dropped");

        if let Ok(()) = handle.await {
            info!("Torrust APIs server on https://{} stopped", bind_addr);
        }
    } else {
        warn!(
            "Could not start Torrust APIs server on https://{}, missing SSL Cert or Key!",
            bind_addr
        );
    }
});

The HTTP tracker shows a warning while starting if an SSL configuration is missing.

We should do the same here for the tracker API.

[josecelano]

Hey @WarmBeer, This issue is related to the PR you are working on.

[josecelano]

We've opened a new issue to panic instead of warning in this case.