Incorret correction when raed is called on File

[yuki24]

Actual (suggesting rand):

File.raed
# => NoMethodError: undefined method `raed' for File:Class
# Did you mean?  rand

Expected (suggesting read):

File.raed
# => NoMethodError: undefined method `raed' for File:Class
# Did you mean?  read

This is because the MethodNameChecker always refers to a set of private method names and it ends up displaying rand whose Levenshtein distance between raed is 1.