Remove accidental device-side statsd CTS tests

Statsd has hostside CTS tests which invoke methods
device-side. These methods actually formed a test module
due to an inappropriately existing AndroidTest.xml file. This is
removed. Also, the word 'Atoms' is dropped from the device app name.

Bug: 73494246
Test: cts-tradefed run cts-dev -m CtsStatsdApp, and make sure it cannot find any
Test: cts-tradefed run cts-dev -m CtsStatsdAtomsApp, and make sure it cannot find any
Test: cts-tradefed run cts-dev -m CtsStatsdHostTestCases, still works
Change-Id: I43c4a9db43203eb00a89ee9fbe63467ce002992b