Update the way we change meteredness of cellular networks in tests. am: 37c10a2252 am: 4fbac43be8

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1582844

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I3e97dc0ccf37c39df9fee74bee8d04f5d226af24
tree: 9f2c14a7c525c659fdb2630007d87b6cf867a951
  1. tests/
  2. Tethering/
  3. .gitignore
  4. OWNERS
  5. PREUPLOAD.cfg
  6. TEST_MAPPING