updatedAt property Null safety

1. wings_data_model
2. wings_data_model
3. Supporter
4. updatedAt property

Supporter class

1. Constructors
2. Supporter
3. Properties
4. avatar
5. birthday
6. country
7. email
8. fcmToken
9. fcmTokenDateTime
10. firebaseUid
11. firstName
12. gender
13. hashCode
14. id
15. interests
16. isCrashlyticsAllowed
17. isMedicalProfileMiningAllowed
18. isOpenForThirdPartyContacts
19. language
20. lastName
21. mobilePhone
22. onBoardingVersionCompleted
23. patients
24. runtimeType
25. updatedAt
26. userId
27. zipCode
28. Methods
29. noSuchMethod
30. rebuild
31. toBuilder
32. toString
33. Operators
34. operator ==