title: upgrade flyway in spring from 5.2.3 to 6.X - org.flywaydb.core.api.callback.FlywayCallback not present
body: <p>I'm using spring boot 2.1.0 and flyway version 5.4.
  In my pom.xml file I didnt mention flyway version and as a result of that mvn downloaded flyway version 5.X : </p>
  
  <pre><code>&lt;dependency&gt;
      &lt;groupId&gt;org.flywaydb&lt;/groupId&gt;
      &lt;artifactId&gt;flyway-core&lt;/artifactId&gt;
  &lt;/dependency&gt;
  </code></pre>
  
  <p>As part of my db upgrade I need to upgrade flyway to at least version 6. I tried adding  tag in the pom.xml and maven indeed install the new version but when starting the app I'm getting the following error : </p>
  
  <pre><code>Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration$FlywayConfiguration': Unexpected exception during bean creation; nested exception is java.lang.TypeNotPresentException: Type org.flywaydb.core.api.callback.FlywayCallback not present
  </code></pre>