Increase tf_preparer_incremental_setup roll out percentage to 10% am: 2c438ed5ea

Original change: https://android-review.googlesource.com/c/platform/tools/asuite/+/3412418

Change-Id: I8a5a75f6a15dd94762b555250363e5384c7377ce
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>