Sample does not highlight the need for application - level pagination handling

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### This issue is for a: (mark with an `x`)
```
- [ ] bug report -> please search issues before submitting
- [ ] feature request
- [X ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
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This being a first touchpoint for many consumers of Azure, I wanted to highlight a naiive assumption I made consuming this API that would have led to data loss in prod.
There is no indication in this getting started that the application is expected to handle HTTP pagination by observing response codes and setting up subsequent read ops. This breaks from Go idioms readers- one reader per blob is a reasonable assumption.
I would suggest calling out the inspection of these HTTP variables in the example - or even mentioning the need in comments- as a warning to API consumers as to the limitations of what the library covers for the application programmer.

I got bit by this. That's on me. I hope we can save someone else from the same issue.