Fix extraneous print of -j. am: 5a1e23a9de am: 7b0a6f2750 am: c1aedcfc3f am: e7a8ade3c8

Original change: https://android-review.googlesource.com/c/platform/system/testing/gtest_extras/+/1403789

Change-Id: I8624d8f2f50da0f794a3431a9ce7f2a4efac9c64