Collector pods can't forward logs to splunk due to self-signed certificate in RHOCP 4

Issue

• Collector pods can't send logs to external Splunk when using secured communication.

• Collector pods stream below logs:

  212023-03-27T19:36:21.892890Z ERROR vector::topology::builder: msg="Healthcheck: Failed Reason." error=Failed to make HTTP(S) request: error trying to connect: error:1416F086:SSL routines:tls_process_server_certificate:certificate verify failed:ssl/statem/statem_clnt.c:1915:: self signed certificate in certificate chain component_kind="sink" component_type="splunk_hec" component_id=splunk_receiver component_name=splunk_receiver
  
  222023-03-27T19:36:22.917402Z ERROR sink{component_kind="sink" component_id=splunk_receiver component_type=splunk_hec component_name=splunk_receiver}:request{request_id=0}:http: vector::internal_events::http_client: HTTP error. error=error trying to connect: error:1416F086:SSL routines:tls_process_server_certificate:certificate verify failed:ssl/statem/statem_clnt.c:1915:: self signed certificate in certificate chain error_type="request_failed" stage="processing"