[Filebeat] CEL input - add http_response_Nxx_total metrics

[andrewkroh]

Describe the enhancement:

Add metrics to the CEL input for observing the HTTP response status code totals. If it is possible to reuse the same code that httpjson uses this would be ideal since we would have near metric parity.

Describe a specific use case for the enhancement or feature:

I would like to be able to monitor the status codes that the input is receiving in HTTP responses.

[elasticmachine]

Pinging @elastic/security-service-integrations (Team:Security-Service Integrations)