Add test to check IpClientLinkObserver stops working when ENOBUFS happens. am: d83a6a8045 am: e424b4da87

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/NetworkStack/+/18816726

Change-Id: Ic0e95f5a2b0ef91d8d234d79f3a6586ee74fc502
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>