update ExtractorFactoryTest for HSUM mode

Moves the assets from /sdcard/test/extractor-* (which doesn't exist if we don't have
a user) to /data/local/tmp/extractor-*. This unblocks HSUM testing in presubmit.

Bug: 383445608
Flag: EXEMPT test fix
Test: atest ExtractorFactoryTest
Change-Id: I5e564828d0a3ced3b8c9a70c474b6c037ceb09a5