title: Json cannot add dependencies
body: <p>Spring Boot version is using version 4.5.2. How can I add Json dependencies to this version?</p>
  
  <p>This error occurs when accessing the current site.</p>
  
  <p><strong>This application has no explicit mapping for /error, so you are seeing this as a fallback.
  Fri Feb 28 03:31:40 KST 2020
  There was an unexpected error (type=Internal Server Error, status=500).
  No converter found for return value of type: class com.example.demo.Dto.TestVo
  org.springframework.http.converter.HttpMessageNotWritableException: No converter found for return value of type: class com.example.demo.Dto.TestVo
      at</strong> </p>
  
  <p>Source code of <code>TestVo</code> class:</p>
  
  <pre><code>package com.example.demo.Dto; 
  
  public class TestVo { 
      private int seq; 
      private String title; 
      private String contents; 
      private String author; 
      private String password; 
      private int reads = 0; 
      private String deleted = "N"; 
  
      @Override 
      public String toString() { 
          return "TestVo [seq=" + seq + ", title=" + title + ", contents=" + contents + ", author=" + author + ", password=" + password + ", reads=" + reads + ", deleted=" + deleted + "]"; 
      } 
  }
  </code></pre>