In SERVER-101781 we added validation to reject $rankFusion stages in view definition pipelines. However, we didn't add any logic to catch $rankFusion being a subpipeline in a stage of a view definition, e.g. a $lookup or a $unionWith. This could potentially trigger a subpipeline cycle similar to that in BF-38095.

While we're at it, we should also disallow $score inside view definition subpipelines to stay in line with SERVER-106204.