fix: proc check only works when there is Procfile available

tests/unit/10_ps-dockerfile.bats

@@ -71,6 +71,14 @@ teardown() {
 }
 
 @test "(ps:scale) dockerfile non-existent process" {
+  run bash -c "dokku --trace ps:scale $TEST_APP non-existent=2"
+  echo "output: $output"
+  echo "status: $status"
+  assert_success
+
+  destroy_app
+  create_app
+  deploy_app dockerfile
   run bash -c "dokku --trace ps:scale $TEST_APP non-existent=2"
   echo "output: $output"
   echo "status: $status"