feature request/refactor: use the `inject` function for dependencies

[Lars Gyrup Brink Nielsen]

inject is more type-safe and should give no issue unless a class is created using its constructor instead of TestBed in test.

inject is better for base classes such as LumberjackLogger and ScopedLumberjackLogger to allow sub-classes to add their own dependencies to their constructor without having to pass the base class' dependencies if they so prefer.