get_commit_date and get_commit_hash now return None if the git command fails instead of Some("") #13217setup_version_info will now re-run when the git commit changes #13329rerun_if_git_changes function was added #13329setup_version_info!(); macro for automated scripts.get_version_info!() no longer requires the user to import rustc_tools_util::VersionInfo and std::env