Expand CircleCI's Sonar Test

[rnveach]

Identified by @nrmancuso when discussing the CircleCI execution,

CircleCI is generating an empty checkstyle config when it does its test run:

# cat target/sonar/checkstyle.xml 
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE module PUBLIC "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN" "https://checkstyle.org/dtds/configuration_1_3.dtd"><!-- Generated by Sonar --><module name="Checker"><module name="SuppressWarningsFilter" /><module name="TreeWalker"><module name="SuppressWarningsHolder"/> <module name="SuppressionCommentFilter" /></module></module>

This makes sense since we are dealing with an blank sonar server in the run.

We should look into injecting some checks and expand to some real tests to ensure the plugin is working correctly.

[rnveach]

Just informational for some possibilities (from @nrmancuso ):

https://sonarqube.inria.fr/sonarqube/web_api/api/qualityprofiles

https://sonarqube.inria.fr/sonarqube/web_api/api/qualityprofiles/exporters
https://sonarqube.inria.fr/sonarqube/web_api/api/qualityprofiles/importers
https://sonarqube.inria.fr/sonarqube/web_api/api/qualityprofiles/restore

Maybe export an already configured server, save it to repo, and then restore it in CI.