Make proc-macro-nested available to product and vendor am: 7ca4181c61

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/proc-macro-nested/+/2476454

Change-Id: Ib436bf13321054e1974298b6175f1da8a664ba08
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>