📍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>

mediator/src/main/java/com/iluwatar/mediator/PartyMemberBase.java

@@ -23,16 +23,14 @@
 
 package com.iluwatar.mediator;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import lombok.extern.slf4j.Slf4j;
 
 /**
  * Abstract base class for party members.
  */
+@Slf4j
 public abstract class PartyMemberBase implements PartyMember {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(PartyMemberBase.class);
-
   protected Party party;
 
   @Override

mediator/src/test/java/com/iluwatar/mediator/PartyImplTest.java

@@ -23,13 +23,13 @@
 
 package com.iluwatar.mediator;
 
-import org.junit.jupiter.api.Test;
-
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoMoreInteractions;
 import static org.mockito.Mockito.verifyZeroInteractions;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Date: 12/19/15 - 10:00 PM
  *
@@ -42,7 +42,7 @@ public class PartyImplTest {
    * other member gets it. Also check members don't get their own actions.
    */
   @Test
-  public void testPartyAction() {
+  void testPartyAction() {
     final var partyMember1 = mock(PartyMember.class);
     final var partyMember2 = mock(PartyMember.class);