Sort noise test results by frequency, not the order they were run

Previously, all the test results were put into the html report that
the touch FW test generated, simply in the order they were run.  This
worked fine until recently when we made it run the noise test in a
randomized order (to improve the validity of the test).  Now the
results are also in a random order, which makes it hard to read since
errors tend to happen in bands of frequencies.  eg: a user might
want to see the details of all the tests around 200khz, but they're
scattered through out the report now.

This CL adds in some logic to filter out the noise tests and sort
them by the frequency of the noise being tested before rending the
report.  Non-noise tests are left un-touched, since they are already
grouped by the type of gesture, which is what we want.

BUG=chromium:509074
TEST=manually tested, the reports look to be in a sane, useful order.

Change-Id: Ib12917e3ab2b64318a0fbde7793c533cfddcf63c
Signed-off-by: Charlie Mooney <charliemooney@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/284866
Reviewed-by: Amirhossein Simjour <asimjour@chromium.org>