docs(sns): remove an unused variable declaration in Archive Policy

[jun1-t]

Describe the issue

Archive Policy parameter in the aws_cdk_sns document has an unused variable declaration.

Currently the documentation says:

---

Example with an archive policy for SQS:

declare const role: iam.Role;
const topic = new sns.Topic(this, 'MyTopic', {
   fifo: true,
   messageRetentionPeriodInDays: 7,
});

---

I think the following is better.

---

Example with an archive policy:

const topic = new sns.Topic(this, 'MyTopic', {
   fifo: true,
   messageRetentionPeriodInDays: 7,
});

---

Removed "for SQS" and "declare const role: iam.Role;".

Links

https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.aws_sns-readme.html#archive-policy

[tim-finnigan]

Thanks for reporting this issue and creating the PR!