Rename UnusedPrivateMember to UnusedPrivateFunction

[BraisGabin]

We were calling UnusedPrivateMember to a rule that only checked functions. So I renamed it to make more clear what it does. Also, it was called like this because time ago this rule handled lots of cases so for that reason I also reduced the number of aliases.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.31%. Comparing base (ac0ee12) to head (05e2d4d).

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #7324   +/-   ##
=========================================
  Coverage     84.31%   84.31%           
  Complexity     4149     4149           
=========================================
  Files           573      573           
  Lines         11888    11888           
  Branches       2458     2458           
=========================================
  Hits          10023    10023           
  Misses          613      613           
  Partials       1252     1252           

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Generated by 🚫 dangerJS against 05e2d4d

[cortinico]

What happened to this one?

[BraisGabin]

We don't need to enable this rule on our own configuration, it is enabled by default. And we don't need any special value for allowedNames on detekt either.