[Code Health] Delete unused code. am: aa510cee am: ebbb9411 am: 51c27ec7...

[Code Health] Delete unused code. am: aa510cee am: ebbb9411 am: 51c27ec7 am: db1b0559 am: 8fb3b844

Original change: https://android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/2746873



Change-Id: Ica5983d164c9340847f44535ebddb7d5e25497a2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>