chore: update dependencies to appease cargo audit

`cargo audit` warns us about a security issue in `hashbrown` crate
(RUSTSEC-2024-0402). We use this as a development dependency, so it
does not affect Firecracker in production. As a result, we don't need to
create a patch release.

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios