Must we have separate Cargo.lock files for hashx and equix benches?

Currently, our hashx and equix benchmarks have their own Cargo.lock files, which we need to update independently. This sometimes causes annoying CI breakage when we forget to do this during the release process.

But tor-proto, on the other hand has benchmarks, and doesn't have its own Cargo.lock file.

IMO we should do the following:

• Identify if there is a good reason for hashx and equix to have their own Cargo.lock files.
• If there is not a good reason:
  • Have hashx and equix use the same Cargo.lock as all the other crates.
• If there is a good reason:
  • Make tor-proto have its own Cargo.lock.
  • Make a maint/cargo-update-all script that updates every Cargo.lock file, and recommend using that script in Release.md.