Profpatsch originally implemented an advisory checker from scratch in
Rust. We now ended up just using cargo-audit for the global checks
exposed via CI and the custom implementation is unused. To clean up
//tools/rust-crates-advisory a bit, we can move the unused parts to his
user directory.
Change-Id: Iacbd27c163edd07c804220fd1b3569c23aebd3e7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7171
Tested-by: BuildkiteCI
Reviewed-by: Profpatsch <mail@profpatsch.de>
8699370fae