title: How Moshi applies the default value of kotlin to the null field of json
body: <h3>Json</h3>
  
  <pre><code>{
      "id": "1",
      "name": "name",
      "email": null
  }
  </code></pre>
  
  <h3>User</h3>
  
  <pre><code>data class User(
      var id: Int = 0,
      var name: String = "",
      var email: String = ""
  )
  </code></pre>
  
  <p>I want to apply default value for null value when parsing json.
  (Apply the above email field as a non-null ""(blank))</p>