Completely remove old non-structured errors and migrate existing ones.

app/views/code_ocean/errors/index.html.slim

@@ -1,19 +0,0 @@
-h1 = CodeOcean::Error.model_name.human(count: 2)
-
-.table-responsive
-  table.table
-    thead
-      tr
-        th = t('errors.index.count')
-        th = t('activerecord.attributes.error.message')
-        th = t('shared.created_at')
-        th = t('shared.actions')
-    tbody
-      - @errors.each do |error|
-        tr
-          td = error.count
-          td = error.message
-          td = l(error.created_at, format: :short)
-          td = link_to(t('shared.show'), execution_environment_error_path(params[:execution_environment_id], error))
-
-p = render('shared/pagination', collection: @errors)

app/views/code_ocean/errors/show.html.slim

@@ -1,4 +0,0 @@
-h1 = CodeOcean::Error.model_name.human
-
-= row(label: 'error.message', value: @error.message)
-= row(label: 'shared.created_at', value: l(@error.created_at, format: :short))