NIFI-7595 Upgrade log4j-core dependency.

[mtien-apache]

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Description of PR

Upgrade log4j-core dependency to 2.13.3.

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[alopresto]

I'm going to let the other CI/CD builds finish, but I have no idea why the failing Groovy test occurred on the MacOS build. That test has been running stably for some time.

[MikeThomsen]

@alopresto I kicked off the CI/CD runs again and we have 4/4.