Upgrade futures-macro to 0.3.30 am: 6ee23ca803

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/futures-macro/+/2942547

Change-Id: I99074eb351392b6457343b0f3bf23a0ea02d5814
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>