Vector shows "error=connection closed before message completed" warnings

Issue

• Vector Pods are showing the following HTTP error. error=connection closed before message completed warnings in their logs:

  $ oc logs collector-2nzx4
  [..]
  2024-01-17T15:09:15.991612Z WARN sink{component_kind="sink" component_id=example_splunk_receiver component_type=splunk_hec_logs component_name=example_splunk_receiver}: vector::internal_events::http_client: HTTP error. error=connection closed before message completed error_type="request_failed" stage="processing" internal_log_rate_limit=true
  2024-01-17T15:09:15.991676Z WARN sink{component_kind="sink" component_id=example_splunk_receiver component_type=splunk_hec_logs component_name=example_splunk_receiver}: vector::sinks::util::retries: Retrying after error. error=Failed to make HTTP(S) request: connection closed before message completed internal_log_rate_limit=true
  2024-01-17T15:09:53.249900Z WARN sink{component_kind="sink" component_id=example_splunk_receiver component_type=splunk_hec_logs component_name=example_splunk_receiver}: vector::internal_events::http_client: HTTP error. error=connection closed before message completed error_type="request_failed" stage="processing" internal_log_rate_limit=true
  [..]
  

• The CollectorHighErrorRate alert is firing as a result of these messages.