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

visitor/src/test/java/com/iluwatar/visitor/CommanderTest.java

@@ -24,7 +24,7 @@
  */
 package com.iluwatar.visitor;
 
-import static org.mockito.Matchers.eq;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.verify;
 
 /**

visitor/src/test/java/com/iluwatar/visitor/SergeantTest.java

@@ -24,7 +24,7 @@
  */
 package com.iluwatar.visitor;
 
-import static org.mockito.Matchers.eq;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.verify;
 
 /**

visitor/src/test/java/com/iluwatar/visitor/SoldierTest.java

@@ -24,7 +24,7 @@
  */
 package com.iluwatar.visitor;
 
-import static org.mockito.Matchers.eq;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.verify;
 
 /**

visitor/src/test/java/com/iluwatar/visitor/UnitTest.java

@@ -24,7 +24,7 @@
  */
 package com.iluwatar.visitor;
 
-import static org.mockito.Matchers.eq;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoMoreInteractions;