Add day-night-mode permission to Shell.

Without the permission "adb shell cmd uimode night <mode>" doesn't work.
Adding the permission to the AndroidManifest file so the shell command
will work.

Bug: 155584597
Test: run `adb shell cmd uimode night <no|yes|auto>`
Change-Id: Ibfb145d762c73bba9de639d4050b9b26e4778cc9