[SPARK-37718][MINOR][DOCS] Demo sql is incorrect
[SPARK-37718][MINOR][DOCS] Demo sql is incorrect

### What changes were proposed in this pull request?

Modify `SELECT * FROM person GROUP BY age HAVING max(age) > 18;`
to
`SELECT age, count(*) FROM person GROUP BY age HAVING max(age) > 18;`

### Why are the changes needed?

Making the demo sql running correctly.

### Does this PR introduce any user-facing change?

NO

### How was this patch tested?

cd docs
SKIP_API=1 bundle exec jekyll build

Closes #34992 from wooplevip/master.

Lead-authored-by: wooplevip <ca31acbe5b7535a236c25249c84d0449414b8aa3@foxmail.com>
Co-authored-by: wooplevip <8f903da0abba6fb89afc06ffc36de48b964f6fd3@foxmail.com>
Signed-off-by: Sean Owen <d519fa33a62684a61ab04b24d26f83452d51b34c@gmail.com>

witgo/spark,srowen/spark,zero323/spark,witgo/spark,rednaxelafx/apache-spark,wangyum/spark,xuanyuanking/spark,holdenk/spark,rednaxelafx/apache-spark,wangyum/spark,WeichenXu123/spark,apache/spark,shaneknapp/spark,witgo/spark,dongjoon-hyun/spark,hvanhovell/spark,wangyum/spark,HyukjinKwon/spark,cloud-fan/spark,holdenk/spark,nchammas/spark,shaneknapp/spark,xuanyuanking/spark,zero323/spark,JoshRosen/spark,WeichenXu123/spark,nchammas/spark,vinodkc/spark,hvanhovell/spark,zero323/spark,xuanyuanking/spark,zero323/spark,xuanyuanking/spark,hvanhovell/spark,shaneknapp/spark,apache/spark,zero323/spark,nchammas/spark,vinodkc/spark,hvanhovell/spark,dongjoon-hyun/spark,shaneknapp/spark,mahak/spark,WeichenXu123/spark,gengliangwang/spark,holdenk/spark,srowen/spark,xuanyuanking/spark,JoshRosen/spark,holdenk/spark,xuanyuanking/spark,gengliangwang/spark,nchammas/spark,witgo/spark,HyukjinKwon/spark,vinodkc/spark,nchammas/spark,dongjoon-hyun/spark,holdenk/spark,mahak/spark,cloud-fan/spark,cloud-fan/spark,gengliangwang/spark,HyukjinKwon/spark,srowen/spark,dongjoon-hyun/spark,mahak/spark,vinodkc/spark,dongjoon-hyun/spark,WeichenXu123/spark,wangyum/spark,HyukjinKwon/spark,vinodkc/spark,witgo/spark,wangyum/spark,wangyum/spark,cloud-fan/spark,rednaxelafx/apache-spark,zero323/spark,ueshin/apache-spark,zzcclp/spark,cloud-fan/spark,dongjoon-hyun/spark,rednaxelafx/apache-spark,zero323/spark,WeichenXu123/spark,mahak/spark,ueshin/apache-spark,apache/spark,dongjoon-hyun/spark,vinodkc/spark,ueshin/apache-spark,mahak/spark,vinodkc/spark,zzcclp/spark,xuanyuanking/spark,ueshin/apache-spark,apache/spark,srowen/spark,zzcclp/spark,holdenk/spark,holdenk/spark,nchammas/spark,wangyum/spark,gengliangwang/spark,ueshin/apache-spark,shaneknapp/spark,gengliangwang/spark,apache/spark,ueshin/apache-spark,zzcclp/spark,HyukjinKwon/spark,cloud-fan/spark,JoshRosen/spark,shaneknapp/spark,gengliangwang/spark,ueshin/apache-spark,shaneknapp/spark,JoshRosen/spark,witgo/spark,WeichenXu123/spark,mahak/spark,apache/spark,zzcclp/spark,witgo/spark,JoshRosen/spark,HyukjinKwon/spark,cloud-fan/spark,gengliangwang/spark,mahak/spark,rednaxelafx/apache-spark,hvanhovell/spark,hvanhovell/spark,HyukjinKwon/spark,zzcclp/spark,JoshRosen/spark,rednaxelafx/apache-spark,hvanhovell/spark,WeichenXu123/spark,JoshRosen/spark,srowen/spark,nchammas/spark,srowen/spark,rednaxelafx/apache-spark,apache/spark,zzcclp/spark,srowen/spark