increase native ssh persist time to half hour
increase native ssh persist time to half hour

original 60s may break ansible connection frequently

for https://github.com/zxwing/premium/issues/1451

Signed-off-by: Mei Lei <d1c6e4e75080176552ef8271b379adabccaa7551@gmail.com>

zstackio/zstack,AlanJinTS/zstack,WangXijue/zstack,MaJin1996/zstack,liningone/zstack,zstackio/zstack,AlanJager/zstack,HeathHose/zstack,zxwing/zstack-1,hhjuliet/zstack,Alvin-Lau/zstack,zstackio/zstack,zsyzsyhao/zstack,WangXijue/zstack,MaJin1996/zstack,zstackorg/zstack,mingjian2049/zstack,camilesing/zstack,MatheMatrix/zstack,liningone/zstack,AlanJager/zstack,hhjuliet/zstack,zxwing/zstack-1,zxwing/zstack-1,winger007/zstack,AlanJager/zstack,HeathHose/zstack,Alvin-Lau/zstack,Alvin-Lau/zstack,MatheMatrix/zstack,liningone/zstack,HeathHose/zstack,winger007/zstack,MatheMatrix/zstack,mingjian2049/zstack,zstackorg/zstack,AlanJinTS/zstack,mingjian2049/zstack,camilesing/zstack,AlanJinTS/zstack,zsyzsyhao/zstack,camilesing/zstack,WangXijue/zstack