[Code Health] Move 'using' out of functions am: 592e8227 am: 8ca3bf21 am:...

[Code Health] Move 'using' out of functions am: 592e8227 am: 8ca3bf21 am: 7c84d737 am: f29b4d38

Original change: https://android-review.googlesource.com/c/platform/packages/modules/DnsResolver/+/2746594



Change-Id: I3ef05be0ffc9f5d13e5fdd165fc05b84d545e9e3
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>