docs: abstract-factory - readme - corrected code description as per real file (iluwatar#1887)

Author: Fiordy

abstract-factory/README.md

@@ -87,24 +87,36 @@ public interface KingdomFactory {
 }
 
 public class ElfKingdomFactory implements KingdomFactory {
+
+  @Override
   public Castle createCastle() {
     return new ElfCastle();
   }
+
+  @Override
   public King createKing() {
     return new ElfKing();
   }
+
+  @Override
   public Army createArmy() {
     return new ElfArmy();
   }
 }
 
 public class OrcKingdomFactory implements KingdomFactory {
+
+  @Override
   public Castle createCastle() {
     return new OrcCastle();
   }
+
+  @Override
   public King createKing() {
     return new OrcKing();
   }
+  
+  @Override
   public Army createArmy() {
     return new OrcArmy();
   }