Use complex type value in task input/output

[vijaynalawade]

What kind of change does this PR introduce? (check one with "x")

[x] Bugfix
[] Feature
[] Code style update (formatting, local variables)
[] Refactoring (no functional changes, no api changes)
[] Other... Please describe:

Fixes: #

What is the current behavior?
For task event, any input/output of type complex object is returned as object containing metadata and a value.
"responseBody":{"metadata":"","value":{"body":"quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto","id":1,"title":"sunt aut facere repellat provident occaecati excepturi optio reprehenderit","userId":1}}
What is the new behavior?
For task event, for complex type object only value is returned.
"responseBody":{"body":"quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto","id":1,"title":"sunt aut facere repellat provident occaecati excepturi optio reprehenderit","userId":1}