Make mPermissionMonitor in ConnectivityService private am: f360aa6058

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2405717

Change-Id: Id3a4e47e3b7c067bbe6426295ddd72bb44973cd6
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>