message: fix(example): fix bug in defaultExample
diff: @@ -16,7 +16,7 @@ function YourForm() {
  {/* include validation with required or other standard HTML validation rules */}
  <input name="exampleRequired" ref={register({ required: true })} />
  {/* errors will return when field validation fails */}
  - {errors.example && '<span>This field is required</span>'}
  + {errors.exampleRequired && <span>This field is required</span>}
  <input type="submit" />
  </form>
  