Fix case statement exception

[jogrogan]

Fix case statements causing a null pointer exception

Example query:

create or replace materialized view ADS."AD_CLICKS$test1" AS SELECT company_name, CASE WHEN company_urn = 'PUBLISHED' THEN NULL ELSE company_urn END FROM PROFILE.COMPANIES;

Result:

- CREATE DATABASE IF NOT EXISTS `PROFILE` WITH ();
- CREATE TABLE IF NOT EXISTS `PROFILE`.`COMPANIES` (`COMPANY_NAME` VARCHAR, `COMPANY_URN` VARCHAR) WITH ('connector'='datagen', 'number-of-rows'='10');
- CREATE DATABASE IF NOT EXISTS `ADS` WITH ();
- CREATE TABLE IF NOT EXISTS `ADS`.`AD_CLICKS` (`CAMPAIGN_URN` VARCHAR, `MEMBER_URN` VARCHAR) WITH ('connector'='blackhole');
- INSERT INTO `ADS`.`AD_CLICKS` (`COMPANY_NAME`, `EXPR_1`) SELECT `COMPANY_NAME`, CASE WHEN `COMPANY_URN` = 'PUBLISHED' THEN NULL ELSE `COMPANY_URN` END FROM `PROFILE`.`COMPANIES`;

Also fixes various checkstyle complaints and adds missing key properties to kafka yaml