chore(deps): update libdd-trace-protobuf digest to 64ad2ed

[dd-octo-sts]

This PR contains the following updates:

Package	Type	Update	Change
libdd-trace-protobuf	dependencies	digest	72fa868 → 64ad2ed

---

Warning

Some dependencies could not be looked up. Check the warning logs for more information.

[dd-octo-sts]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: Cargo.lock

Command failed: cargo update --config net.git-fetch-with-cli=true --manifest-path crates/datadog-trace-agent/Cargo.toml --workspace
error: rustup could not choose a version of cargo to run, because one wasn't specified explicitly, and no default is configured.
help: run 'rustup default stable' to download the latest stable release of Rust and set it as your default toolchain.