message: fix: ensure only nromalize a scoped slot when it is present
diff: @@ -12,9 +12,11 @@ export function normalizeScopedSlots (
  } else {
  res = {}
  for (const key in slots) {
  + if (slots[key]) {
  res[key] = normalizeScopedSlot(slots[key])
  }
  }
  + }
  // expose normal slots on scopedSlots
  for (const key in normalSlots) {
  res[key] = () => normalSlots[key]
  