Function build_job_env 

pub fn build_job_env(
    base_env: &[(String, String)],
    default_vars: &HashMap<String, String>,
    job: &JobSpec,
    secrets: &SecretsStore,
    host_workdir: &Path,
    container_workdir: &Path,
    container_root: &Path,
    run_id: &str,
    host_env: &HashMap<String, String>,
) -> Vec<(String, String)>