Use version 2.x of protobuf crate am: be5c27de05 am: 34fade917c am: 1f6c25d621

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/grpcio/+/2501997

Change-Id: I24398fa8f6965e5c5d2809b0157829f4699d4d89
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>