Disable unused Python 2 variant. am: 5cd0b3ded4 am: f1b3028b2f am: 70a3fb1cd3

Original change: https://android-review.googlesource.com/c/platform/external/python/oauth2client/+/2221452

Change-Id: I53cbdd496998077f688d785431f80bdbfaa6fb31
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>