deps: update dependency org.easymock:easymock to v4 (#640)

* deps: update dependency org.easymock:easymock to v4

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pom.xml

@@ -15,7 +15,7 @@
 
   <properties>
     <logback.version>1.2.10</logback.version>
-    <easymock.version>3.6</easymock.version>
+    <easymock.version>4.3</easymock.version>
     <truth.version>1.1.3</truth.version>
     <logging.version>3.6.0</logging.version>
     <slf4j.version>1.7.32</slf4j.version>