pub fn new(task_id: &str, missing_platform_env: Vec<String>) -> Option<Self> {
        if missing_platform_env.is_empty() {
            return None;
        }
        Some(Self {
            task_id: task_id.to_owned(),
            missing_platform_env,
        })
    }
Construct a new warning for a given task with the
Returns `None` if there are no missing platform environment variables
crates/turborepo-lib/src/task_graph/visitor/error.rs