fix(db): remove bad attachments

destroy attachments with blobs that doesn't exist

lib/tasks/deployment/20220728062218_cleanup_attachments.rake

@@ -0,0 +1,21 @@
+namespace :after_party do
+  desc 'Deployment task: cleanup_attachments'
+  task cleanup_attachments: :environment do
+    puts "Running deploy task 'cleanup_attachments'"
+
+    invalid_attachments = ActiveStorage::Attachment.where.missing(:blob)
+    invalid_attachments_count = invalid_attachments.size
+
+    if invalid_attachments.any?
+      invalid_attachments.destroy_all
+      puts "#{invalid_attachments_count} with blob that doesn't exist have been destroyed"
+    else
+      puts "No attachments with blob that doesn't exist found"
+    end
+
+    # Update task as completed.  If you remove the line below, the task will
+    # run with every deploy (or every time you call after_party:run).
+    AfterParty::TaskRecord
+      .create version: AfterParty::TaskRecorder.new(__FILE__).timestamp
+  end
+end