Test cases are failing for 4.0.1 version

[akshaypatil1]

Fantastic job people, this package really helps a lot. Recently I migrate my complete application. Now installed react-notifications-component version 4.0.1 . Old test cases which were working, now fails with following error -

TypeError: this.add is not a function
Store.addNotification({
............^

I appreciate your help. Thank you.