fix: pom.xml to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JAVA-ORGAPACHECOMMONS-10734078

Author: snyk-bot

pom.xml

@@ -55,7 +55,7 @@
         <junit.version>4.13.2</junit.version>
         <mockito.version>3.8.0</mockito.version>
         <easymock.version>4.2</easymock.version>
-        <mavenVersion>3.9.6</mavenVersion>
+        <mavenVersion>3.9.8</mavenVersion>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>