Upgrade nix to 0.28.0 am: 33265a2e3a am: 716864b0c3

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/nix/+/3032729

Change-Id: I59e318c690556d3c1f62347e7b96d8d2ca096d2c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>