Fix memory leak in hiddenapi_test

Forgot to put an instance of ZipArchive into unique_ptr.

Bug: 64382372
Test: m test-art-host-gtest-hiddenapi_test
Change-Id: I3bed0a20e55018f4e904750e0f4aeded8f93c4cc
diff --git a/tools/hiddenapi/hiddenapi_test.cc b/tools/hiddenapi/hiddenapi_test.cc
index 1f37f40..6348405 100644
--- a/tools/hiddenapi/hiddenapi_test.cc
+++ b/tools/hiddenapi/hiddenapi_test.cc
@@ -46,12 +46,13 @@
                                               const std::vector<std::string>& extra_args,
                                               ScratchFile* out_dex) {
     std::string error;
-    ZipArchive* jar = ZipArchive::Open(GetTestDexFileName("HiddenApi").c_str(), &error);
+    std::unique_ptr<ZipArchive> jar(
+        ZipArchive::Open(GetTestDexFileName("HiddenApi").c_str(), &error));
     if (jar == nullptr) {
       LOG(FATAL) << "Could not open test file " << GetTestDexFileName("HiddenApi") << ": " << error;
       UNREACHABLE();
     }
-    ZipEntry* jar_classes_dex = jar->Find("classes.dex", &error);
+    std::unique_ptr<ZipEntry> jar_classes_dex(jar->Find("classes.dex", &error));
     if (jar_classes_dex == nullptr) {
       LOG(FATAL) << "Could not find classes.dex in test file " << GetTestDexFileName("HiddenApi")
                  << ": " << error;