Try to fix issue building mvn cache in conourse pipeline

concourse/tasks/build-mvn-cache.sh

@@ -5,9 +5,6 @@ workdir=`pwd`
 cd ${workdir}/sts4/headless-services
 ./mvnw -DskipTests package
 
-cd ${workdir}/sts4/headless-services/jdt-ls-extension
-../mvnw -DskipTests package
-
 timestamp=`date +%s`
 tarfile=${workdir}/out/sts4-mvn-cache-${timestamp}.tar.gz
 tar -czvf ${tarfile} -C ${HOME} .m2/repository

headless-services/pom.xml

@@ -15,6 +15,7 @@
 		<module>concourse-language-server</module>
 		<module>spring-boot-language-server</module>
 		<module>bosh-language-server</module>
+		<module>jdt-ls-extension</module>
 	</modules>
 
 </project>