AuthBasicCredentials constructor Null safety

1. conduit_core
2. conduit
3. AuthBasicCredentials
4. AuthBasicCredentials constructor

AuthBasicCredentials class

1. Constructors
2. AuthBasicCredentials
3. Properties
4. hashCode
5. password
6. runtimeType
7. username
8. Methods
9. noSuchMethod
10. toString
11. Operators
12. operator ==