Only compile plugins when testing, don't package

Change-Id: I7812ee99036e8b5f5615f0c2fc0feb1c9e71f142
Reviewed-on: http://gerrit.dmdirc.com/2433
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>

build-tests.xml

         <clover-setup initstring="${clover.init.string}"/>
     </target>
 
-    <target name="compile-for-tests" depends="clean,with.clover,jar"/>
+    <target name="compile-for-tests" depends="clean,with.clover,compile"/>
 
 </project>