Upgrade log4j to confluent-log4j

[Clarence97]

JIRA ticket here: https://confluentinc.atlassian.net/browse/DGS-1888?page=com.atlassian.jira.plugin.system.issuetabpanels%3Aall-tabpanel

[OneCricketeer]

Is this still needed? Ref #2275

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