Merge "Decouple Ipv6UpstreamRule with Ipv6DownstreamRule" into main am: 2a6a7359b7

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2711576

Change-Id: I46b48a93f9920b860a036a92152d2eee1c013df0
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>