Forwarding logs to Kafka using Chained certificates fails with error "state=error: certificate verify failed (unable to get local issuer certificate)" in RHOCP 4.6

Issue

• Forwarding logs to Kafka using Chained certificates fails with the error:

  ...
  2020-11-27 12:26:36 +0000 [warn]: suppressed same stacktrace
  2020-11-27 12:26:36 +0000 [warn]: Send exception occurred: SSL_connect returned=1 errno=0 state=error: certificate verify failed (unable to get local issuer certificate)
  2020-11-27 12:26:36 +0000 [warn]: Exception Backtrace : /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/ssl_socket_with_timeout.rb:69:in `connect_nonblock'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/ssl_socket_with_timeout.rb:69:in `initialize'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/connection.rb:130:in `new'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/connection.rb:130:in `open'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/connection.rb:101:in `block in send_request'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/instrumenter.rb:23:in `instrument'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/connection.rb:100:in `send_request'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/broker.rb:200:in `send_request'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/broker.rb:44:in `fetch_metadata'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/cluster.rb:427:in `block in fetch_cluster_info'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/cluster.rb:422:in `each'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/cluster.rb:422:in `fetch_cluster_info'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/cluster.rb:402:in `cluster_info'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/cluster.rb:102:in `refresh_metadata!'
  /usr/local/share/gems/gems/ruby-kafka-1.1.0/lib/kafka/cluster.rb:56:in `add_target_topics'
  /usr/local/share/gems/gems/fluent-plugin-kafka-0.13.1/lib/fluent/plugin/kafka_producer_ext.rb:91:in `initialize'
  /usr/local/share/gems/gems/fluent-plugin-kafka-0.13.1/lib/fluent/plugin/kafka_producer_ext.rb:60:in `new'
  /usr/local/share/gems/gems/fluent-plugin-kafka-0.13.1/lib/fluent/plugin/kafka_producer_ext.rb:60:in `topic_producer'
  /usr/local/share/gems/gems/fluent-plugin-kafka-0.13.1/lib/fluent/plugin/out_kafka2.rb:232:in `write'
  /usr/local/share/gems/gems/fluentd-1.7.4/lib/fluent/plugin/output.rb:1125:in `try_flush'
  /usr/local/share/gems/gems/fluentd-1.7.4/lib/fluent/plugin/output.rb:1431:in `flush_thread_run'
  /usr/local/share/gems/gems/fluentd-1.7.4/lib/fluent/plugin/output.rb:461:in `block (2 levels) in start'
  /usr/local/share/gems/gems/fluentd-1.7.4/lib/fluent/plugin_helper/thread.rb:78:in `block in thread_create'
  2020-11-27 12:26:36 +0000 [warn]: failed to flush the buffer. retry_time=6 next_retry_seconds=2020-11-27 12:27:11 +0000 chunk="5b5020a1f38cef2ace97184cd6d81ae9" error_class=OpenSSL::SSL::SSLError error="SSL_connect returned=1 errno=0 state=error: certificate verify failed (unable to get local issuer certificate)"
  ...