Add an option to only use a strict leading `>` to keep texts being included in a callout

Use case or problem

I’d like to remove the line break shown above, but meanwhile, keep the second test being outside the callout.
When I delete this empty line, it would automatically be part of the callout, even without a leading > mark. This mechanism prevents me from just using a line break to finish editing a callout.

Proposed solution

Hoping to, or at least add an option to restrict users to use a strict leading > format to assign texts being included in a callout. If so, since no leading > exists before the second test, the callout would end without including it as my expectation.
Or as what Admonition does, introducing code block structure to make a separate.

Thanks for reading.