Exclude junit classes from cts-api-signature-test

junit classes were accidentaly included in the library indirectly via
compatibility-device-util. Since this will prevent the API tests from
detecting that junit classes are not provided by the platform, moving
compatibility-device-util library from the test lib into the
system-annotation test where the functionality of the lib is actually
used.

Test: mma -j under cts/tests/signature is successful
Test: unzip -l out/target/common/obj/APPS/CtsCurrentApiSignatureTestCases_intermediates/classes.jar
does not show any junit class under org.junit package.

Change-Id: I9187a3572d2aa6d0d25cc15b75376f21d3db7477
4 files changed