Object type for patches?

[paradox460]

I've read across the docs, and can't seem to figure out how I could go about changing a config that expects an "object" (key-value pairs) in a reliable way.

Specifically, I'm looking to edit the paper config for $.entities.spawning.alt-item-despawn-rate.items. This is an object type, and the default configs helpfully include an example of cobblestone: 300. I would like to remove that, and then add my own key(s) and values as appropriate.

Adding the new values seems simple enough, just use a put operation. But removing the old value has stymied me