Make zipapex test support multiple-execution

Some run-tests execute run-test-jar multiple times. This could cause
issues with setting up the zipapex due to the already existing symlink
causing a new symlink to be created within the zipapex dir. If two
tests with multiple executions both happened to pick the same
temp-directory name this could cause 'ln' to exit non-zero failing the
test. To fix this we simply detect and continue cases where the
zipapex symlink already exists.

Test: ./test/testrunner/run_build_test_target.py art-linux-bionic-x64-zipapex
Bug: 135507613
Change-Id: Id2f4d5c75ef8d35011eb25e87fd400e6bc3b9eca
1 file changed