Reorder translations and add missing prefixes

- files should be prefixed with code_ocean/
- the markdown editor is part of the application (helper)

app/views/exercises/_code_field.html.slim

@@ -1,5 +1,5 @@
 .mb-3
-  = form.label(attribute, label, class: 'form-label')
+  = form.label(attribute, class: 'form-label')
   = form.text_area(attribute, class: 'code-field form-control', rows: 16, style: 'display:none;')
   = render partial: 'editor_edit', locals: {exercise: @exercise}
   .card.border-warning.p-2.my-2