Update TEST_MAPPING am: bb68c9e927

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/percent-encoding/+/2108564

Change-Id: Ief17594aa6391be05f9d8fe82edebd8543abf08f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>