Issue #130: remove surplus maven property, which leads to wrong checkstyle version displayed during run

Author: Patrick Mayweg

checkstyle-sonar-plugin/pom.xml

@@ -15,7 +15,6 @@
   <description>Checkstyle is a code analyser to help programmers write Java code that adheres to a coding standard.</description>
 
   <properties>
-    <checkstyle.version>7.3</checkstyle.version>
     <maven.checkstyle.plugin.version>2.17</maven.checkstyle.plugin.version>
     <maven.sevntu.checkstyle.plugin.version>1.23.0</maven.sevntu.checkstyle.plugin.version>
   </properties>