Merge pull request #5 from salesforce/upgrade-checkstyle

Update pom.xml

Author: rmichela

pom.xml

@@ -44,7 +44,7 @@
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <maven.compiler.source>1.8</maven.compiler.source>
     <maven.compiler.target>1.8</maven.compiler.target>
-    <checkstyle.version>8.8</checkstyle.version>
+    <checkstyle.version>8.20</checkstyle.version>
     <maven-checkstyle-plugin.version>3.0.0</maven-checkstyle-plugin.version>
     <maven.version>3.3.9</maven.version>
   </properties>