bug: pseudo_class_pool doesn't work when an analysis returns an object with more than one class

[Gootjes]

This line contains head() without 1 meaning it gets the top 10 classes for an object instead of only the first one... Can you fix it to say head(..., n = 1) ? :) https://github.com/cjvanlissa/tidySEM/blame/a75ec5e85330931799fc0af36b54850ba5a6c624/R/mixture-pseudo_class.R#L84