Sharded time-series listIndexes should report the view's namespace

If I run the listIndexes command on a time-series view, normally it returns the name of the view as "ns":

> db.runCommand({listIndexes: 'example'})

{

        "id" : NumberLong(0),

        "ns" : "test.example",

        "firstBatch" : [

                ...

        ]

}

But if it's a sharded time-series view, instead it replies with the name of the buckets collection:

> db.runCommand({listIndexes: 'example'})

{

        "id" : NumberLong(0),

        "ns" : "test.system.buckets.example",

        "firstBatch" : [

                ...

        ]

}

I think it should return the name of the view in both cases, since the buckets collection is an implementation detail.

Sounds like this happens because mongos translates a listIndexes request on the view, to listIndexes on the buckets collection. So it needs to also translate the response.