Improve typing for FunctionsHttpError errors

[JulienLecoq]

In the supabase js library, the following code will "create" a response.error.context field of an any type.

const response = await supabaseClient
  .functions
  .invoke('my-edge-function', {
    body,
  })
    
if (response.error !== null && response.error instanceof FunctionsHttpError) {
  response.error.context // any type
}

It would be cool instead if the context could be typed.