set cron timezone to Shanghai

Former-commit-id: b1f05d796dce95cae1b19c5729ccd4d8da8219c1

ci/jenkins/Jenkinsfile

+String cron_timezone = "TZ=Asia/Shanghai"
 String cron_string = BRANCH_NAME == "master" ? "H 0 * * *" : ""
 cron_string =  BRANCH_NAME == "0.5.1" ? "H 1 * * *" : cron_string
 
 pipeline {
     agent none
 
-    triggers { cron(cron_string) }
+    triggers {
+        cron("${cron_timezone}
+            ${cron_string}")
+    }
 
     options {
         timestamps()