Remove PRODUCT_ALWAYS_PREOPT_EXTRACTED_APK.

This was added by r.android.com/513843 to force dexpreopt some GMS core
modules even if dexpreopt is disabled, to avoid some memory usage
regression. We no longer need it because dexpreopt is never disabled on
production builds.

Bug: 313505540
Test: m
Change-Id: Iff7f1d340a3ecd64cdc3d2f83f9c37c109a81fda