code: function updateIn(record, accessor, updator, ctx) {
      if (!updator) {
          return record;
      }
      return mutate(record, accessor, MutateType.updateIn, updator, ctx);
  }
docs: Update a deep child by old value
  @param record The object to update, it can be a plain object or a class instance
  @param accessor A lambda function to get the key path, support dot, [''], [""], [1], **do not** support dynamic variable, function call, e.g.
  @param updator A update function that take the old value and return the new value.
  @param ctx Dynamic key map.