This is very similar to another question I often hear:
How do you without seeming “rude” get people to stick to not make actions when you collect data.
My approach is to remind the group gather data is not about solutioning, it's about taking (and looking at) a snapshot of what happened. It can be a mix of objective data and reflective (how we felt about it). Not about generating insight yet.
The advantage to slow it down a bit is it encourages full participation and mutual understanding. Jumping to solutions skips that step and could creating solutions that are not sustainable and even hindering your improvement process.
If the person has a lot of energy (or is being an asshole) I'd just capture what that person says so we can move on. I'd suggest we put the "action" in a parking lot and be clear that we'll continue with the format and keep his suggestion in mind when we decide what to do.
Playing devil's advocate, maybe that suggestion is what the team needs. So I make that the person that want to "jump" knows we appreciate the idea.