linstor: Fix a file handle resource leak opening template.properties (#13091)

Author: rp-

plugins/storage/volume/linstor/src/main/java/com/cloud/hypervisor/kvm/storage/LinstorStorageAdaptor.java

@@ -585,8 +585,8 @@ private static boolean isSystemTemplate(KVMPhysicalDisk disk) {
         Path propFile = diskPath.getParent().resolve("template.properties");
         if (Files.exists(propFile)) {
             java.util.Properties templateProps = new java.util.Properties();
-            try {
-                templateProps.load(new FileInputStream(propFile.toFile()));
+            try (FileInputStream in = new FileInputStream(propFile.toFile())) {
+                templateProps.load(in);
                 String desc = templateProps.getProperty("description");
                 if (desc != null && desc.startsWith("SystemVM Template")) {
                     return true;