Migrate to cargo_embargo. am: 8725301739 am: 6973449a66 am: 42f297dca9

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/shared_child/+/2838082

Change-Id: Ic2065eee31bb3418e6f17ea35e47e79b3d7fd31f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>