Timestamp warning in collector pods forwarding logs to Splunk in RHOCP 4

Issue

• Vector pods show the below warning log:

  WARN sink{component_kind="sink" component_id=splunk component_type=splunk_hec_logs component_name=splunk}: vector::internal_events::splunk_hec::sink: Timestamp was not found. Deferring to Splunk to set the timestamp. internal_log_rate_limit=true
  WARN sink{component_kind="sink" component_id=splunk component_type=splunk_hec_logs component_name=splunk}: vector::internal_events::splunk_hec::sink: Internal log [Timestam was not found. Deferring to Splunk to set the timestamp.] is being rate limited.