Use hyphen rather than underscore in cargo2android.json. am: f08f333d7c am: 640c851fc5 am: 9b488e41c2

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/grpcio-sys/+/2822012

Change-Id: I5f4029046892b67380302c275f8d50ea3052f542
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>