BiometricUserVerifier constructor Null safety

1. nevis_mobile_authentication_sdk
2. nevis_mobile_authentication_sdk
3. BiometricUserVerifier
4. BiometricUserVerifier constructor

BiometricUserVerifier class

1. Constructors
2. BiometricUserVerifier
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. noSuchMethod
8. onValidCredentialsProvided
9. toString
10. verifyBiometric
11. Operators
12. operator ==