pub fn new(base_delay: Duration, max_delay: Duration) -> Self {
        Backoff {
            base_delay,
            current_delay: base_delay,
            max_delay,
        }
    }
Create a backoff with base_delay (first delay) and max_delay (maximum delay possible).
prover/crates/lib/prover_job_processor/src/backoff_and_cancellable.rs