Move gcstress test configurations to use the CC collector.

These test configurations used to use the SS (semi-space) collector:
- art-gcstress-gcverify
- art-interpreter-gcstress
- art-optimizing-gcstress
- art-jit-gcstress
Have them use the CC (concurrent copying) collector instead, as it is
our main collector now.

Test: art/test/testrunner/run_build_test_target.py art-gcstress-gcverify
Test: art/test/testrunner/run_build_test_target.py art-interpreter-gcstress
Test: art/test/testrunner/run_build_test_target.py art-optimizing-gcstress
Test: art/test/testrunner/run_build_test_target.py art-jit-gcstress
Bug: 62611253
Change-Id: I04fe75c00e10a3a6926460d8728411fac220c7e6