Update improper text regarding cacheControl changes in v6

**Describe the content issue**:
A clear and concise description of what the content issue is. Is there content missing or is there incorrect content?

`cacheControl` was [removed in v6](https://docs.amplify.aws/gen1/angular/build-a-backend/storage/storage-v5-to-v6-migration-guide/#:~:text=cacheControl,by%20the%20runtime.) but we still have the FAQ section at the bottom of [this page](https://docs.amplify.aws/gen1/angular/build-a-backend/storage/download/#frequently-asked-questions:~:text=You%20can%20pass,the%20latest%20version.) stating it can be used.

See amplify-js issue [# 13581](https://github.com/aws-amplify/amplify-js/issues/13581)