Exclude ScanningSettingsTest tests

While we mitigated the system wide presubmit blockage due to failing
test, it's been brought to attention that the test has been flaky for
sometime. And still uses junit3, which means it hasn't been maintained
for sometime.

Bug: 293934372
Test: N/A
Change-Id: Iea48daf39e8d40667f635e68b4c8e341abf4341a