Add `POST_NOTIFICATIONS` permission to app's manifest

Since we updated the target SDK version to 33 in
3f05b7fc1f, we should request
notifications permissions to continue allowing the user to receive
journal changes and certificate notifications

app/src/main/AndroidManifest.xml

@@ -23,6 +23,7 @@
     <uses-permission android:name="android.permission.READ_SYNC_STATS"/>
     <uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS"/>
     <uses-permission android:name="android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS"/>
+    <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
 
     <!-- account management permissions not required for own accounts since API level 22 -->
     <uses-permission android:name="android.permission.AUTHENTICATE_ACCOUNTS" android:maxSdkVersion="22"/>