build: sync Cargo.lock for the git-remote-gitlawb dependencies

Adding serde_json and chrono to crates/git-remote-gitlawb/Cargo.toml updated
Cargo.lock locally, but the lockfile lives at the repo root and was never
staged. Every CI job builds with --locked, so all seven compiling jobs failed
immediately with "cannot update the lock file ... because --locked was passed".

Author: Vasanthdev2004