Migrate to cargo_embargo. am: 93b21ad4eb am: f02ee5a184

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/async-task/+/2796114

Change-Id: I53e6bbef3145d965a0b266de6e1b3eb9530e2c05
Signed-off-by: Automerger Merge Worker <[email protected]>