Metrics involved:

• desc
• ns
• op
• originatingCommand
• state
• totalOperationTimeElapsedSecs
• type

We shouldn't have a partially declared object that is in an invalid state. We need to figure out some solution that doesn't involve a constructor a lot of parameters.

The final "build" function should take a service context so that the user of the builder doesn't have to care about the cumulative metrics object.

It should also work for the children of the ShardingDataTransformInstanceMetrics class.