📍Use lombok, reformat, and optimize the code (#1560)

* Use lombok, reformat, and optimize the code

* Fix merge conflicts and some sonar issues

Co-authored-by: va1m <va1m@email.com>

dirty-flag/src/main/java/com/iluwatar/dirtyflag/World.java

@@ -37,7 +37,7 @@ public class World {
   private final DataFetcher df;
 
   public World() {
-    this.countries = new ArrayList<String>();
+    this.countries = new ArrayList<>();
     this.df = new DataFetcher();
   }