Update the zstd crate from version 0.9.0 to 0.13.0, removing the TODO
comment blocking the upgrade. The dependency update also includes
related bumps to zstd-safe and zstd-sys crates, along with the
addition of pkg-config as a new transitive dependency.
Change-Id: I6a6a696459075f5ee56f448e87286b6ec39b26d3
Reviewed-on: https://cl.snix.dev/c/snix/+/30640
Tested-by: besadii
Reviewed-by: Florian Klink <flokli@flokli.de>