Disable unused Python 2 variant. am: e90ad5e404 am: 7e6e982b8e am: e679be899e

Original change: https://android-review.googlesource.com/c/platform/external/python/cachetools/+/2221305

Change-Id: Idb9d993235ec92ed80c45e97d499f2c49d9672bc
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>