Clean up rust_test_host TEST_MAPPING after default update am: 12f47a0789 am: 3d0062c9a4

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/pin-project-internal/+/1590752

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: If2ff0172f626a4b2a69be73d5d1b54376d33190e