Remove art_apex and art_apex_test module type.

These types don't seem to be doing anything special since
https://android-review.googlesource.com/c/platform/art/+/1862813.

(credits to eakammer@ for discovering the code)

Test: CI
Change-Id: Ifb95e20c8471601dd877aac351040887ccaacf1e
2 files changed