title: Jackson OffsetDateTime serialization Z instead of +00:00 timezone?
body: <p>I'm using Spring Boot with the following ObjectMapper:</p>
  
  <pre><code>@Bean
  public ObjectMapper objectMapper()
  {
      final ObjectMapper mapper = new ObjectMapper();
  
      mapper.enable(SerializationFeature.INDENT_OUTPUT);
  
      mapper.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);  
      mapper.setDateFormat(new StdDateFormat().withColonInTimeZone(true)); // Makes no difference to output
  
      mapper.findAndRegisterModules();
  
      return mapper;
  }
  </code></pre>
  
  <p>When OffsetDateTimes are serialized and returned in responses, they have a format like this:</p>
  
  <pre><code>"2020-02-28T12:28:29.01Z"
  "2020-02-28T12:36:21.885Z"
  
  </code></pre>
  
  <p>I would have expected the timezone information at the end to look like this instead:</p>
  
  <pre><code>"2020-02-28T10:41:25.287+00:00"
  </code></pre>
  
  <p>Is there something I'm missing or doing wrong here, or anyway I can get the timezone information serialized as the <code>+00:00</code> format instead of <code>885Z</code> format? </p>
  
  <p>Many thanks!</p>