[Java] Upgrade to Mockito 4.4.0.

Author: mjpt777

build.gradle

@@ -44,7 +44,7 @@ def toolchainLauncher = javaToolchains.launcherFor {
 
 def checkstyleVersion = '9.3'
 def hamcrestVersion = '2.2'
-def mockitoVersion = '4.3.1'
+def mockitoVersion = '4.4.0'
 def junitVersion = '5.8.2'
 def jmhVersion = '1.34'
 def agronaVersion = '1.14.0'