RetryRule fromRetryRuleWithContent() {
        requireNonNull(retryRuleWithContent, "retryRuleWithContent");
        requireNonNull(fromRetryRuleWithContent, "fromRetryRuleWithContent");
        return fromRetryRuleWithContent;
    }
Returns the {@link RetryRuleWithContent} converted from the {@link RetryRule} of this config.
core/src/main/java/com/linecorp/armeria/client/retry/RetryConfig.java