Authentication and session creation
It is not technically wrong. In OOP languages you can encounter this sort of thing (a private method apparently only used once) especially in loops. Or if you want a specific part of the algorithm to not be overrideable, etc. Generally spoken however, I see no reason to do it in your example. The code was clear and now has way more clutter.
Whenever you repeat yourself in a class, whenever you use copy paste from another class, is most oftentimes an indication that you could abstract the code to a set of smaller functions / objects. 
With regards to the tool reporting a high ABC rank: those tools do not IMHO replace common sense. You should never sacrifice readability and conciseness for the sake of a better score. This is a case where your code quality tool might have too rigid settings, or perhaps there is more code in the inspected scope that is better suited or in more need of refactoring.