Prometheus work with blackbox exporter to fetch sample data

Question

We are using prometheus operator which works as expected, We want now to add the blackbox exporter

I've installed in the same namespace like Prometheus with https://github.com/helm/charts/tree/master/stable/prometheus-blackbox-exporter

Now I've update the config (values.yaml)and install the chart with the update new values like:

 helm upgrade --install bbe stable/prometheus-blackbox-exporter -f values.yaml -n po

Took the defaults...

  targets:
    - name: example                    # Human readable URL that will appear in Prometheus / AlertManager
      url: http://example.com/healthz  # The URL that blackbox will scrape
      labels: {}                       # List of labels for ServiceMonitor. Overrides value set in `defaults`
      interval: 60s                    # Scraping interval. Overrides value set in `defaults`
      scrapeTimeout: 60s               # Scrape timeout. Overrides value set in `defaults`
      module: http_2xx                 # Module used for scraping. Overrides value set in `defaults`

https://github.com/helm/charts/blob/master/stable/prometheus-blackbox-exporter/values.yaml#L137

I've configure the target to use blackbox exporter like following

https://github.com/helm/charts/blob/master/stable/prometheus-operator/values.yaml#L1872

additionalScrapeConfigs:
  - job_name: 'blackbox'
    static_configs:
    - targets: ['localhost:9115']

Get svc to the namespace returns the follwing:

bbe-prometheus-blackbox-exporter    ClusterIP  100.26.213.43 9115/TCP       19h

if I change the config to use the svc like following

additionalScrapeConfigs:
  - job_name: 'blackbox'
    static_configs:
    - targets: ['bbe-prometheus-blackbox-exporter:9115']

I see that it up on the target,

However, still we doesn't see any of the example metric in Prometheus UI, Any idea what could be missing here? should I search of other metric property and not example?

btw, I run port-forward for blackbox, and use http://localhost:9115/metrics and I dont see the example entry there (see many others which come by default) , any idea what could be wrong? how should I search for it?

In addition, if I take one entry from the blackbox exporter properties which I got when calling to http://localhost:9115/metric like go_info and run execute I see the following go_info{instance="bbe-prometheus-blackbox-exporter:9115", job="blackbox", version="go1.13.4"} which I guess prometheus is connect to blackbox exporter, however I dont see the metric example which I configure in blackbox exporter

update

I've use the additionalScrapeConfig property according to the comments of @FL3SH and I see that in the target. my question is for instance how should I query one of the entries (in Prometheus ui) ,lets say I want to know if cncf endpoint is up and running.