Fixed a race condition when attaching network request am: ca9e31e5

Original change: https://android-review.googlesource.com/c/platform/frameworks/opt/telephony/+/2091574



Change-Id: Ibaa2f15028714e70bc1f687844989095474c1144
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>