Workaround for ls processes being leaked by lps4e

See:
  - https://bugs.eclipse.org/bugs/show_bug.cgi?id=549904
  - https://www.pivotaltracker.com/story/show/167519460

headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/jdt/ls/JavaProjectsServiceWithFallback.java

@@ -10,6 +10,7 @@
  *******************************************************************************/
 package org.springframework.ide.vscode.boot.jdt.ls;
 
+import java.time.Duration;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
@@ -79,6 +80,7 @@ public class JavaProjectsServiceWithFallback implements JavaProjectsService {
 
 		this.mainServiceInitialized = this.server
 				.onInitialized(main.initialize())
+				.timeout(Duration.ofSeconds(5))
 				.toFuture();
 
 		this.server.onShutdown(() -> {