KAFKA-5229: Reflections logs excessive warnings when scanning classpaths
KAFKA-5229: Reflections logs excessive warnings when scanning classpaths

changed the reflections log level to ERROR.
And tested it, now the warning logs are not shown up during the start of Kafka connect.
ewencp could you please review the changes.

Author: Bharat Viswanadham <bharatv@us.ibm.com>

Reviewers: Ewen Cheslack-Postava <ewen@confluent.io>

Closes #3072 from bharatviswa504/KAFKA-5229

guozhangwang/kafka,Ishiihara/kafka,MyPureCloud/kafka,richhaase/kafka,sslavic/kafka,gf53520/kafka,sebadiaz/kafka,ollie314/kafka,Chasego/kafka,apache/kafka,themarkypantz/kafka,guozhangwang/kafka,Esquive/kafka,guozhangwang/kafka,lindong28/kafka,MyPureCloud/kafka,Esquive/kafka,TiVo/kafka,ErikKringen/kafka,MyPureCloud/kafka,lindong28/kafka,gf53520/kafka,mihbor/kafka,richhaase/kafka,TiVo/kafka,themarkypantz/kafka,mihbor/kafka,sebadiaz/kafka,Ishiihara/kafka,TiVo/kafka,Ishiihara/kafka,noslowerdna/kafka,gf53520/kafka,KevinLiLu/kafka,themarkypantz/kafka,lindong28/kafka,MyPureCloud/kafka,sslavic/kafka,ollie314/kafka,sebadiaz/kafka,noslowerdna/kafka,Chasego/kafka,themarkypantz/kafka,Chasego/kafka,noslowerdna/kafka,Chasego/kafka,Esquive/kafka,airbnb/kafka,KevinLiLu/kafka,sslavic/kafka,noslowerdna/kafka,sslavic/kafka,apache/kafka,TiVo/kafka,airbnb/kafka,Esquive/kafka,ErikKringen/kafka,ErikKringen/kafka,apache/kafka,guozhangwang/kafka,mihbor/kafka,ErikKringen/kafka,sebadiaz/kafka,airbnb/kafka,KevinLiLu/kafka,richhaase/kafka,richhaase/kafka,airbnb/kafka,ollie314/kafka,gf53520/kafka,Ishiihara/kafka,apache/kafka,KevinLiLu/kafka,mihbor/kafka,lindong28/kafka,ollie314/kafka