This is a follow-up for #66.
The reconciler for the new HorizontalRunnerDeploymentAutoscaler had a terrible flaw that prevented the controller to fail launching due to an error like:
```
indexer conflict: map[field:.metadata.controller:{}]
```
This fixes that, while adding `integration_test.go` to verify its actually fixed and prevent regression in the future.
Yusuke Kuoka