sencha robots: add soundstream sanity check

Checks the output of the soundstream dmeo. This assumes the demo is setup
to run one iteration of the input loop with a 2000 sample audio buffer.

Bypass-Presubmit-Reason: no CI tests (but soon)

Change-Id: If313611dd932c8beda8231feb4a7dd4a30c4dc35
2 files changed