AuthAdapterAbstract constructor Null safety

1. irte_engine
2. auth_adapter.interface
3. AuthAdapterAbstract
4. AuthAdapterAbstract constructor

AuthAdapterAbstract class

1. Constructors
2. AuthAdapterAbstract
3. Properties
4. endpoint
5. hashCode
6. runtimeType
7. Methods
8. authenticate
9. noSuchMethod
10. post
11. toString
12. Operators
13. operator ==