ExtractorUnitTest libstagefright_foundation to static

Use static version of libstagefright_foundation instead of shared.
This sets up the test to run on older releases and resolves startup
issues with the test using symbols that are only defined in later
Android releases.

Bug: 402724393
Test: atest ExtractorUnitTest
Flag: TEST_ONLY
Change-Id: I447f573c1c58dfacad191d6c06133f79824910a6