Fix AssistDataRequesterTest Flakiness am: 947d06eeb9

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24458208

Change-Id: I277b06aa8408f02a0eebe6dcc4fb2751e246c603
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>