[WifiNotification] Only clean up the notification from Wifi

Wifi Stack is using "Android" as package name. cancelAll will clean all
the notification from system. We should only clean the notifications with Wifi tag.

Bug: 189363587
Test: atest FrameworksWifiTests
Change-Id: Iab6c4c3689f2d9a785de6dff89ee18c606daa8f9
2 files changed