Clean up more test configurations (Part 2).

Remove the following configurations, as they are disabled on
our continuous testing infrastructure:
- art-interpreter-gcstress
- art-optimizing-gcstress
- art-jit-gcstress
- art-read-barrier
- art-read-barrier-gcstress

This CL should not be submitted before cl/213456896 is merged.

Test: n/a
Bug: 62611253
Change-Id: Ide02a5ea86bd22810d8efa3491fbd670fde2e3f1