FP: Private method is never called

[ben-manes]

The method CaffeineConfiguration.$deserializeLambda$() is private and never called.
The private method CaffeineConfiguration.$deserializeLambda$() is never explicitly called
and probably should be removed. If it's designed to be called via reflection or via method
handles API, it's a good practice to annotate it by some annotation which will explicitly
signal that the method is necessary.

Seems to not recognize Java serialization yet. Unfortunately required due to the JSR's interface.