ci(checkstyle): switch to Google style

Author: thomasleplus

pom.xml

@@ -239,6 +239,12 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-checkstyle-plugin</artifactId>
         <version>3.6.0</version>
+        <configuration>
+          <configLocation>google_checks.xml</configLocation>
+          <includeTestSourceDirectory>true</includeTestSourceDirectory>
+          <consoleOutput>true</consoleOutput>
+          <failsOnError>true</failsOnError>
+        </configuration>
       </plugin>
       <plugin>
         <groupId>org.owasp</groupId>