Values.MergeShardsInputSourceRepresents the input for MergeShards.
type nonrec t = {streamName : StreamName.t option;The name of the stream for the merge.
*)shardToMerge : ShardId.t;The shard ID of the shard to combine with the adjacent shard for the merge.
*)adjacentShardToMerge : ShardId.t;The shard ID of the adjacent shard for the merge.
*)streamARN : StreamARN.t option;The ARN of the stream.
*)streamId : StreamId.t option;Not Implemented. Reserved for future use.
*)}