Debounce the onLoadMore function so that it only fires once per scroll event (#18790)
Debounce the onLoadMore function so that it only fires once per scroll event (#18790)

* Debounce the onLoadMore function so that it only fires once per scroll event

react-native's SectionList seems to have a bug where it calls the `onLoadMore` function
twice instead of once. This causes an unnecessary RPC call. Adds an if so as to skip this
if we're already waiting on the results of an RPC call.

* Delete console.log :)

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