Remove stale/duplicate log output config
This stale log output config remains from ElasticSearch which is no longer deployed. We should be using the OpenSearch output plugin, since the API has diverged from ElasticSearch. By removing this config, we will rely on the KA default config for OpenSearch, which contains some additional settings, including around buffering.
Since the config we are removing was overriding the OpenSearch config, we should hopefully see some improvements in stability.