fix typo in processor-api developer guide docs (#7689)
fix typo in processor-api developer guide docs (#7689)

Fixed a small typo on the Processor API page of the Kafka Streams developer guide docs. ("buildeer" changed to "builder")

Reviewers: Bill Bejeck <5c404be01b63927a28df603569da1321e84406a6@gmail.com>
Chasego/kafka,TiVo/kafka,noslowerdna/kafka,apache/kafka,Chasego/kafka,TiVo/kafka,guozhangwang/kafka,lindong28/kafka,sslavic/kafka,lindong28/kafka,lindong28/kafka,guozhangwang/kafka,Chasego/kafka,sslavic/kafka,sslavic/kafka,noslowerdna/kafka,noslowerdna/kafka,apache/kafka,apache/kafka,lindong28/kafka,Chasego/kafka,TiVo/kafka,sslavic/kafka,guozhangwang/kafka,apache/kafka,noslowerdna/kafka,TiVo/kafka,guozhangwang/kafka