without this change we have 2 different properties. One is `spring.sleuth.metric` and the other is `spring.sleuth.metrics`. with this change we're introducing conditionality on `spring.sleuth.metric.enabled` fixes #477
without this change we have 2 different properties. One is `spring.sleuth.metric` and the other is `spring.sleuth.metrics`. with this change we're introducing conditionality on `spring.sleuth.metric.enabled` fixes #477