@Override
    public long getRetryInterval() {
        // Calls to getRetryInterval are always guarded by a call to retryRequest (using the same thread).
        // A thread local allows this retry handler to be thread safe and support dynamic retry intervals
        return retryInterval.get();
    }
A {@link ServiceUnavailableRetryStrategy} that supports delayed retries on any response types.

@author bjorncs
http-utils/src/main/java/ai/vespa/util/http/hc4/retry/DelayedResponseLevelRetryHandler.java