Improve test setup and teardown for integration tests

[ScottG489]

These tests can be affected by the existing state of previously created containers, volumes, etc. We should more properly "namespace" any containers or volumes we create. This would probably involve deleting any of these resources that exist before our tests run and also doing this after the test is finished. We can't guarantee our teardowns will always be called, so we have to make sure the environment for the docker resources we're working with is clean before we start. We should still make a best effort to clean up at teardown.

To "namespace" docker resources, we should prepend any containers or volumes we create with a string so we can more easily find and delete them and aren't accidentally deleting resources we don't manage.