Axum HTTP tracker: remove temporary `status` endpoint

Parent issue: https://github.com/torrust/torrust-tracker/issues/160

It was introduced only for testing and debugging during the [scaffolding setup](https://github.com/torrust/torrust-tracker/pull/180).