CompositeHealthContributorConfiguration has a createContributor that checks if the provided map has a single element and, if that is the case, the raw indicator is returned.
CompositeReactiveHealthContributorConfiguration however, has a createComposite that doesn't do such check. As a result, you end up with a CompositeReactiveHealthContributor even if there is only one indicator for a given type.
Comment From: snicoll
Ignore me. I was reviewing a PR that was calling the wrong method in the reactive variant 🤦♂️