[Storage] Add stress tests for Storage libraries using azure-core-v2

[JonathanGiles]

We want to ensure the quality of our libraries running on client-core / azure-core-v2 by running stress tests. This issue tracks the goal of having a good range of stress tests running against the storage service, with more being added as necessary, as well as being updated to use the convenience APIs when they become available later in the year.

[vcolin7]

Opened this draft PR that adds the foundation for stress tests on core-v2 and runs download tests without fault injector for the time being.

[vcolin7]

More tests shall trickle in during the next couple of weeks.