dependencies: Upgrade mockito 3.5 to 4.5 (#2316)

* refactor: move tests of leader-followers into correct package

* dep: remove version constraint for Mockito in acyclic-visitor

* dep: remove version constraint for Mockito in caching

* chore: cleanup mockito-core import on some POMs

* dep: upgrade core.mocktio 3.5.6 to 4.5.1

"- org.mockito.Mockito#verifyZeroInteractions an alias of verifyNoMoreInteractions"
https://github.com/mockito/mockito/commit/caf35b24e2764df0498469526ecb3e7ec68a0430

caching/src/main/java/com/iluwatar/caching/database/MongoDb.java

@@ -53,6 +53,10 @@ public class MongoDb implements DbManager {
   private MongoClient client;
   private MongoDatabase db;
 
+  void setDB(MongoDatabase db) {
+    this.db = db;
+  }
+
   /**
    * Connect to Db. Check th connection
    */

caching/src/test/java/com/iluwatar/caching/database/MongoDbTest.java

@@ -33,7 +33,6 @@ import org.bson.Document;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mock;
-import org.mockito.internal.util.reflection.Whitebox;
 
 import static com.iluwatar.caching.constants.CachingConstants.ADD_INFO;
 import static com.iluwatar.caching.constants.CachingConstants.USER_ID;
@@ -56,10 +55,8 @@ class MongoDbTest {
   @BeforeEach
   void init() {
     db = mock(MongoDatabase.class);
-    Whitebox.setInternalState(mongoDb, "db", db);
+    mongoDb.setDB(db);
     userAccount = new UserAccount(ID, NAME, ADDITIONAL_INFO);
-
-
   }
 
   @Test