Revert "CLDC-4402: add log incomplete questions method"

This reverts commit a16e208ac1.

app/models/log.rb

@@ -392,13 +392,6 @@ private
     form.subsections.all? { |subsection| subsection.complete?(self) || subsection.not_displayed_in_tasklist?(self) }
   end
 
-  # useful for testing, call .send("incomplete_questions") to see why a log is not complete
-  def incomplete_questions
-    form.subsections
-        .filter { |subsection| !subsection.complete?(self) && subsection.displayed_in_tasklist?(self) }
-        .flat_map { |subsection| subsection.questions.filter { |question| !question.completed?(self) && question.displayed_to_user?(self)  && !question.derived?(self) } }
-  end
-
   def all_subsections_unstarted?
     not_started_statuses = %i[not_started cannot_start_yet]
     form.subsections.all? { |subsection| not_started_statuses.include? subsection.status(self) }