Merge "Add a test case that a Border Router sends a UDP message to Thread device" into main am: b206809a64

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2966916

Change-Id: Iedbcead1905af38abd699b0d4349f03979d9fa7b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>