Update TestUtils.java

Author: rickenwang

QCloudCosXml/cosxml/src/androidTest/java/com/tencent/cos/xml/core/TestUtils.java

@@ -197,6 +197,6 @@ public static void sleep(long time) {
     }
 
     public static String localParentPath() {
-        return Environment.getExternalStorageDirectory().getAbsolutePath();
+        return getContext().getApplicationContext().getFilesDir().getAbsolutePath();
     }
 }