Dexter: Add TEST_MAPPING

Run dexmaker's CTS tests as well as JVMTI tests. The latter is
somewhat overkill, but easier/less errorprone than manually
selecting the tests that use slicer.

Test: atest --test-mapping tools/dexter
Change-Id: Icaa25f9021186d7948b5300f9dbc2a5c4f34b4a3