Starts adding tests for the scripts

- First target: run-ravenwood-tests.sh

- Also remove "-b" from run-ravenwood-tests.sh, which was broken

Bug: 292141694
Flag: TEST_ONLY
Test: $ANDROID_BUILD_TOP/frameworks/base/ravenwood/scripts/run-ravenwood-tests.sh -s

Change-Id: I244e610f60b02507250968391877a7f8aa7cef47