Use posix basename instead of glibc am: 62434518b2 am: f79c211cf2 am: e265ca9bbe am: 7e7e6d3521 am: cf9f64b762

Original change: https://android-review.googlesource.com/c/platform/system/testing/gtest_extras/+/1797187

Change-Id: I5862ebba6407bda197ee8e1dd090c1486e7a4de3