[Code Health] Move 'using' out of functions am: 592e8227 am: eaa76e62 am:...

[Code Health] Move 'using' out of functions am: 592e8227 am: eaa76e62 am: a797e27c am: 91c20ac0 am: 3e62dfa4

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



Change-Id: Ie939130ef27532d8668494b0d19be5a846a87d00
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>