Jacoco and test-jar still runs even with -DskipTests

With the command `mvn package -P windows -DskipTests` the test-jar for main still generates and it should not.



Looks like we just need to manually add the variable to configuration for `maven-jar-plugin` in the main pom.xml

Also jacoco should only run when tests are run.  It's currently running also even if `-Dskiptests` is set.



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### Versions<!--  (please complete the following information)-->

 - Operating System: Windows 11

 - Browser Version: <!--  e.g. Chrome 19, Firefox 61, Safari, NOTE: OpenRefine does not support IE but works OK in most cases -->

 - JRE or JDK Version: JDK 21

 - OpenRefine: master branch



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