Add missing config properties to the trpc handler

Features
1

createNetlifyTRPCHandler in @netlify/sdk/ui/functions/trpc(JS SDK) has no way for a user to define the values of 5 properties for fetchRequestHandler

  • allowBatching
  • allowMethodOverride
  • onError
  • maxBatchSize
  • responseMeta

I only need to be able to set allowMethodOverride to true, so I can use POST requests for queries. However, the remaining 4 properties could be useful to someone else, so it makes sense to ask for all of them to be user-configurable rather than just the one I need.

The onError property does have an implementation in createNetlifyTRPCHandler, but it’s not user-configurable.