ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488
ZOOKEEPER-3817: suppress log4j SmtpAppender related CVE-2020-9488

Author: Mate Szalay-Beko <symat@apache.org>

Reviewers: Enrico Olivelli <07e410ee8dc2e6e114c721434b1411e048f4444b@apache.org>

Closes #1346 from symat/ZOOKEEPER-3817

(cherry picked from commit f6b54a6cd227ac37f28803f45d7287c7fd3a8142)
Signed-off-by: Enrico Olivelli <07e410ee8dc2e6e114c721434b1411e048f4444b@apache.org>

naver/arcus-zookeeper,naver/arcus-zookeeper,naver/arcus-zookeeper,naver/arcus-zookeeper,naver/arcus-zookeeper,naver/arcus-zookeeper,naver/arcus-zookeeper,naver/arcus-zookeeper