Remove PairProgrammingExerciseFeedback

* Remove view, controller, routes & policy for PairProgrammingExerciseFeedback
* Keep model & database table

app/views/pair_programming_exercise_feedbacks/_form.html.slim

@@ -1,31 +0,0 @@
-= form_for(@uef) do |f|
-  div
-    h1 id="exercise-headline"
-      = t('activerecord.models.user_exercise_feedback.one') + " " + @exercise.title
-  = render('shared/form_errors', object: @uef)
-  p
-    == t('pair_programming_exercise_feedback.description')
-  .mb-3
-    h5.mt-4 = t('pair_programming_exercise_feedback.difficulty')
-    = f.collection_radio_buttons :difficulty, @texts, :first, :last  do |b|
-      .form-check
-        label.form-check-label
-          = b.radio_button(class: 'form-check-input')
-          = b.text
-    h5.mt-4 = t('pair_programming_exercise_feedback.working_time')
-    = f.collection_radio_buttons :user_estimated_worktime, @times, :first, :last  do |b|
-      .form-check
-        label.form-check-label
-          = b.radio_button(class: 'form-check-input')
-          = b.text
-    - if PairProgramming23Study.participate?(current_user, @exercise) && !current_contributor.programming_group?
-      h5.mt-4 = t('pair_programming_exercise_feedback.reason_work_alone')
-      = f.collection_radio_buttons :reason_work_alone, @reasons, :first, :last  do |b|
-        .form-check
-          label.form-check-label
-            = b.radio_button(class: 'form-check-input')
-            == b.text
-
-    = f.hidden_field(:exercise_id, :value => @exercise.id)
-    = f.hidden_field(:submission_id, :value => @submission.id)
-  .actions = render('shared/submit_button', f: f, object: @uef)

app/views/pair_programming_exercise_feedbacks/new.html.slim

@@ -1 +0,0 @@
-= render('form')