Merge branch '2.2.x'

See gh-21127

Author: philwebb

spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/jar/JarFile.java

@@ -115,6 +115,7 @@ public JarFile(File file) throws IOException {
 	 */
 	JarFile(JarFile parent) throws IOException {
 		super(parent.rootFile.getFile());
+		super.close();
 		this.parent = parent;
 		this.rootFile = parent.rootFile;
 		this.pathFromRoot = parent.pathFromRoot;