Set default time zone (#3006)

Date type date problem in spring serializing Java
Solution: Spring serializes Java's date type date problem

Co-authored-by: gabry.wu <gabrywu@apache.org>
Co-authored-by: dailidong <dailidong66@gmail.com>

dolphinscheduler-api/src/main/resources/application-api.properties

@@ -23,6 +23,9 @@ server.servlet.session.timeout=7200
 
 server.servlet.context-path=/dolphinscheduler/
 
+# Set time zone
+spring.jackson.time-zone=GMT+8
+
 # file size limit for upload
 spring.servlet.multipart.max-file-size=1024MB
 spring.servlet.multipart.max-request-size=1024MB