Fix null ptr with seralizing EnvironBean

[osoriano]

Summary

In the previous PR (#1923), Teletraan now sends notifications on stage creation/deletion. However, the jackson mapper throws a null pointer exception since the notify_authors getter/setter uses a primitive value, but the underlying value uses a wrapper (e.g. Boolean instead of boolean).

The notify_authors is the only field affected. Move the getter/setter to the wrapped type.

Testing Done

• Verified the null pointer exception was being thrown in the dev environment
• Verified after apply the change, the notification was actually sent