* JAVA-14723 Convert spring-mvc-basics-4 to Spring Boot project and update articles
* JAVA-14723 Refactoring and remove unused files
* JAVA-14723 remove the WEB-INF and migrate jsp to html
* JAVA-14723 Add back the removed test and rename the test into: ArticleViewerControllerWithRequiredAttributeIntegrationTest
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Co-authored-by: timis1 <noreplay@yahoo.com>