docs: public RetryInterceptorBuilder<T> backOffPolicy(BackOffPolicy policy) {
  		Assert.isNull(this.retryOperations,
  				"cannot set the back off policy when a custom retryOperations has been set");
  		Assert.isTrue(!this.backOffOptionsSet,
  				"cannot set the back off policy when the back off policy options have been set");
  		this.retryTemplate.setBackOffPolicy(policy);
  		this.templateAltered = true;
  		this.backOffPolicySet = true;
  		return this;
  	}