Make 0 as invalid value for `min_children` in `has_child` query

[mayya-sharipova]

0 for min_children option in has_child query doesn't make sense, because:

1. It is ambiguous. Does it mean to match only parents that either have children matching the specified constraints or no have no children at all.
2. It currently behaves as a value of 1, that is if there is no at least 1 child matching a specified constrained, a parent document is not returned.

For these reasons, we should make 0 value as invalid value.

Related #21224

[elasticmachine]

Pinging @elastic/es-search-aggs

[kevinaud]

I'm interested in working on this

[rajeshggwp]

Is anyone still working on this? If not can I pick this?

[mayya-sharipova]

@rajeshggwp Sorry, we do have an open PR for this: #33073

[shoaib4330]

Is someone working on it? The issue is still open, I plan on working on it.

[mayya-sharipova]

@shoaib4330 Sorry, we have a stalled PR opened for it. I think we will just finish that PR.