aosp: reenable the filtered out test point in atest

A more systematic fix. Now for each test point, we create temp file
copies at temp dir and explicitly set the file permission of these temp
files. This should bypass the issue that test build artifact file
permission are not guaranteed. Because we will generate these test
storage files on the fly at run time.

Bug: b/324459233
Test: atest aconfig_storage_file.test
Change-Id: Iaa7083be6cc49421090ab4c74e54c4bcf8e35801