Disable Python 2 variant, but keep sources filegroup. am: 665a6ab3f7 am: 4cd48834ec am: 89c6609d06 am: 3a8f39dd56 am: 3d632e231a

Original change: https://android-review.googlesource.com/c/platform/external/python/httplib2/+/2221133

Change-Id: I26c0a8d08c6a6f9f81d4ba7ee7b769dd0fecf2d8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>