Rename the expected-output text file in built TradeFed ART run-tests.

Test suite packages (e.g. `android-mts.zip`) flatten tests artifacts
into a single `testcases` directory, therefore each included file must
have a unique name. Have the build system rename every `expected.txt`
file to a unique name when building TradeFed-style ART run-tests.

Test: atest art-run-test-001-HelloWorld
Bug: 147812905
Change-Id: I0d433d0a611cb5214ae366e2c1af214e41c127f0
616 files changed