Revert "Disable JDT LS classpath support"

This reverts commit 07b7c313f4.

vscode-extensions/vscode-spring-boot/scripts/preinstall.sh

@@ -15,13 +15,12 @@ curl https://raw.githubusercontent.com/textmate/java.tmbundle/master/Syntaxes/Ja
 rm -fr ${workdir}/jars
 mkdir -p ${workdir}/jars
 
-# DISABLED in master for now:
 # Use maven to build jdt ls extension
-#cd ../../headless-services/org.springframework.tooling.jdt.ls.extension
-#../mvnw \
-#    -Djdt.ls.updatesite=file://${HOME}/git/eclipse.jdt.ls/org.eclipse.jdt.ls.repository/target/repository\
-#    clean package
-#cp target/*.jar ${workdir}/jars/jdt-ls-extension.jar
+cd ../../headless-services/org.springframework.tooling.jdt.ls.extension
+../mvnw \
+    -Djdt.ls.updatesite=file://${HOME}/git/eclipse.jdt.ls/org.eclipse.jdt.ls.repository/target/repository\
+    clean package
+cp target/*.jar ${workdir}/jars/jdt-ls-extension.jar
 
 # Use maven to build fat jar of the language server
 cd ../../headless-services/spring-boot-language-server