Migrate to cargo_embargo. am: 9cda7e65d3 am: ad00557201

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/tokio-test/+/2832820

Change-Id: I3f940207f173548f5bc9480882311dded9c28047
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>