add post_notification permission to manifest

so the package can send notifications on T+

Bug: 194833441
Change-Id: I760b7fce2fe23a4a2c9db3b21b4cd0e6c2c769d0

AndroidManifest.xml

@@ -47,6 +47,7 @@
     <uses-permission android:name="android.permission.CALL_PHONE" />
     <uses-permission android:name="android.permission.DOWNLOAD_WITHOUT_NOTIFICATION" />
     <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
 
     <!--  Optional features -->
     <uses-feature android:name="android.hardware.camera" android:required="false" />