Clean up some file open/close usages in the test runner.
Clean up some file open/close usages in the test runner.

da-woods/cython,da-woods/cython,scoder/cython,cython/cython,da-woods/cython,scoder/cython,cython/cython,da-woods/cython,scoder/cython,scoder/cython,cython/cython,cython/cython