HDDS-10597. Use MutableGauge for threshold based SafeModeMetrics.

[sadanand48]

What changes were proposed in this pull request?

Right now, we use MutableCounterLong for threshold metrics like numContainerWithOneReplicaReportedThresholdand when it is updated in setNumContainerWithOneReplicaReportedThreshold(long val) it incremented instead of setting the accurate value. This makes no sense as this field is a threshold and shouldn't be used as a counter. The JMX output show cumulative addition of these threshold values which makes no sense

What is the link to the Apache JIRA

https://issues.apache.org/jira/browse/HDDS-10597

How was this patch tested?

Manually